Lecture: Information processing. Receiving information What is the difference between receiving information and receiving a message
Information is information about something.
The concept and types of information, transmission and processing, search and storage of information
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Information is, definition
Information is any information received and transmitted, stored by various sources. Information is the totality of information about the world around us, about all kinds of processes taking place in it, which can be perceived by living organisms, electronic machines and other information systems.
- This significant information about something, when the form of their presentation is also information, that is, it has a formatting function in accordance with its own nature.
Information is everything that can be supplemented by our knowledge and assumptions.
Information is information about something, regardless of the form of their presentation.
Information is the mental product of any psychophysical organism, produced by it when using some means, called the means of information.
Information is information perceived by a person and (or) special. devices as a reflection of the facts of the material or spiritual world in the process of communication.
Information is data organized in such a way that makes sense to the person dealing with it.
Information is the value a person puts into data based on the known conventions used to represent it.
Information is information, explanation, presentation.
Information is any data or information that anyone is interested in.
Information is information about objects and phenomena of the environment, their parameters, properties and state, which are perceived by information systems (living organisms, control machines, etc.) in the process of life and work.
The same information message (newspaper article, announcement, letter, telegram, reference, story, drawing, radio broadcast, etc.) may contain a different amount of information for different people - depending on their previous knowledge, on the level of understanding of this messages and interest in it.
In cases where they talk about automated work with information through any technical devices, they are not interested in the content of the message, but in how many characters this message contains.
In relation to computer data processing, information is understood as a certain sequence of symbolic designations (letters, numbers, encoded graphic images and sounds, etc.) that carry a semantic load and are presented in a form understandable to a computer. Each new character in such a sequence of characters increases the information volume of the message.
Currently, there is no single definition of information as a scientific term. From the point of view of various fields of knowledge, this concept is described by its specific set of features. For example, the concept of "information" is basic in the course of computer science, and it is impossible to define it through other, more "simple" concepts (just as in geometry, for example, it is impossible to express the content of the basic concepts of "point", "line", "plane" through simpler concepts).
The content of the basic, basic concepts in any science must be explained by examples or identified by comparing them with the content of other concepts. In the case of the concept of "information", the problem of its definition is even more complicated, since it is a general scientific concept. This concept is used in various sciences (computer science, cybernetics, biology, physics, etc.), while in each science the concept of "information" is associated with different systems of concepts.
The concept of information
In modern science, two types of information are considered:
Objective (primary) information is the property of material objects and phenomena (processes) to generate a variety of states, which through interactions (fundamental interactions) are transmitted to other objects and imprinted in their structure.
Subjective (semantic, semantic, secondary) information is the semantic content of objective information about objects and processes of the material world, formed by the human mind with the help of semantic images (words, images and sensations) and fixed on some material carrier.
In the everyday sense, information is information about the surrounding world and the processes taking place in it, perceived by a person or a special device.
Currently, there is no single definition of information as a scientific term. From the point of view of various fields of knowledge, this concept is described by its specific set of features. According to the concept of K. Shannon, information is the removed uncertainty, i.e. information that should remove, to one degree or another, the uncertainty that the consumer has before they are received, expand his understanding of the object with useful information.
From Gregory Beton's point of view, the elementary unit of information is a "caring difference" or an effective difference for some larger perceiving system. Those differences that are not perceived, he calls "potential", and perceived - "active". "Information consists of indifferent differences" (c) "Any perception of information is necessarily an acquisition of information about a difference." From the point of view of computer science, information has a number of fundamental properties: novelty, relevance, reliability, objectivity, completeness, value, etc. The science of logic is primarily involved in the analysis of information. The word "information" comes from the Latin word informatio, which in translation means information, clarification, familiarization. The concept of information was considered by ancient philosophers.
Before the industrial revolution, defining the essence of information remained the prerogative of mainly philosophers. Further, the science of cybernetics, which was new at that time, began to consider issues of information theory.
Sometimes, in order to comprehend the essence of a concept, it is useful to analyze the meaning of the word that denotes this concept. Elucidation of the internal form of the word and study of the history of its use can shed unexpected light on its meaning, eclipsed by the usual "technological" use of this word and modern connotations.
The word information entered the Russian language in the Petrine era. For the first time it is recorded in the "Spiritual Regulations" of 1721 in the meaning of "representation, concept of something". (In European languages, it was fixed earlier - around the 14th century.)
Based on this etymology, information can be considered any significant change in form, or, in other words, any materially fixed traces formed by the interaction of objects or forces and amenable to understanding. Information is thus a converted form of energy. The carrier of information is a sign, and the way of its existence is interpretation: revealing the meaning of a sign or a sequence of signs.
The meaning can be an event reconstructed from the sign that caused its occurrence (in the case of "natural" and involuntary signs, such as traces, evidence, etc.), or a message (in the case of conventional signs characteristic of the sphere of language). It is the second kind of signs that makes up the body of human culture, which, according to one of the definitions, is "a set of non-hereditarily transmitted information."
Messages may contain information about facts or interpretation of facts (from Latin interpretatio, interpretation, translation).
A living being receives information through the senses, as well as through reflection or intuition. The exchange of information between subjects is communication or communication (from lat. communicatio, message, transmission, derived in turn from lat. communico, to make common, to inform, talk, connect).
From a practical point of view, information is always presented as a message. An informational message is associated with a message source, a message recipient, and a communication channel.
Returning to the Latin etymology of the word information, let's try to answer the question of what exactly the form is given here.
It is obvious that, firstly, some sense, which, being initially formless and unexpressed, exists only potentially and must be "built" in order to become perceived and transmitted.
Secondly, to the human mind, which is brought up to think structurally and clearly. Thirdly, a society that, precisely because its members share these meanings and share them, gains unity and functionality.
Information as an expressed reasonable meaning is knowledge that can be stored, transmitted and be the basis for the generation of other knowledge. The forms of knowledge conservation (historical memory) are diverse: from myths, annals and pyramids to libraries, museums and computer databases.
Information - information about the world around us, about the processes taking place in it, which are perceived by living organisms, control machines and other information systems.
The word "information" is Latin. For a long life, its meaning has undergone evolution, sometimes expanding, sometimes narrowing its boundaries to the limit. At first, the word "information" meant: "representation", "concept", then - "information", "message transmission".
In recent years, scientists have decided that the usual (generally accepted) meaning of the word "information" is too elastic, vague, and gave it such a meaning: "a measure of certainty in a message."
Information theory was brought to life by the needs of practice. Its origin is associated with the work of Claude Shannon "Mathematical Theory of Communication", published in 1946. The foundations of information theory are based on the results obtained by many scientists. By the second half of the 20th century, the globe was buzzing with transmitted information, running through telephone and telegraph cables and radio channels. Later, electronic computers appeared - information processors. And for that time, the main task of information theory was, first of all, to increase the efficiency of the functioning of communication systems. The difficulty in the design and operation of means, systems and communication channels is that it is not enough for the designer and engineer to solve the problem from physical and energy positions. From these points of view, the system can be the most perfect and economical. But it is also important when creating transmission systems to pay attention to how much information will pass through this transmission system. After all, information can be quantified, calculated. And they act in such calculations in the most usual way: they abstract from the meaning of the message, as they renounce concreteness in the arithmetic operations familiar to all of us (as from the addition of two apples and three apples they pass to the addition of numbers in general: 2 + 3).
The scientists said they "completely ignored human evaluation of information." To a sequence of 100 letters, for example, they assign meaning to information, regardless of whether that information makes sense and whether, in turn, practical application makes sense. The quantitative approach is the most developed branch of information theory. According to this definition, a collection of 100 letters—a 100-letter phrase from a newspaper, Shakespeare's play, or Einstein's theorem—has exactly the same amount of information.
This quantification of information is highly useful and practical. It corresponds exactly to the task of the communications engineer, who must convey all the information contained in the submitted telegram, regardless of the value of this information for the addressee. The communication channel is soulless. One thing is important for the transmitting system: to transmit the required amount of information in a certain time. How to calculate the amount of information in a particular message?
The assessment of the amount of information is based on the laws of probability theory, more precisely, it is determined through the probabilities of events. This is understandable. The message has value, carries information only when we learn from it about the outcome of an event that has a random character, when it is to some extent unexpected. After all, the message about the already known does not contain any information. Those. if, for example, someone calls you on the phone and says: “It is light during the day and dark at night,” then such a message will surprise you only with the absurdity of the statement of the obvious and well-known, and not with the news that it contains. Another thing, for example, the result of the race at the races. Who will come first? The outcome here is difficult to predict. The more the event of interest to us has random outcomes, the more valuable the message about its result, the more information. An event message that has only two equally possible outcomes contains one piece of information called a bit. The choice of the unit of information is not accidental. It is associated with the most common binary way of encoding it during transmission and processing. Let us try, at least in the most simplified form, to imagine that general principle of the quantitative evaluation of information, which is the cornerstone of the entire theory of information.
We already know that the amount of information depends on the probabilities of certain outcomes of an event. If an event, as scientists say, has two equally likely outcomes, this means that the probability of each outcome is 1/2. This is the probability of getting heads or tails when tossing a coin. If an event has three equally likely outcomes, then the probability of each is 1/3. Note that the sum of the probabilities of all outcomes is always equal to one: after all, one of all possible outcomes will definitely come. An event, as you understand, can have unequal outcomes. So, in a football match between strong and weak teams, the probability of a strong team winning is high - for example, 4/5. The probability of a draw is much less, for example 3/20. The probability of defeat is very small.
It turns out that the amount of information is a measure of reducing the uncertainty of some situation. Different amounts of information are transmitted over communication channels, and the amount of information passing through the channel cannot exceed its capacity. And it is determined by how much information passes here per unit of time. One of the characters in Jules Verne's novel The Mysterious Island, journalist Gideon Spillet, was telephoning a chapter from the Bible so that his competitors could not use the telephone. In this case, the channel was loaded completely, and the amount of information was equal to zero, because the subscriber received information known to him. This means that the channel was idle, passing a strictly defined number of pulses, without loading them with anything. Meanwhile, the more information each of a certain number of pulses carries, the more fully the channel bandwidth is used. Therefore, it is necessary to intelligently encode information, to find an economical, stingy language for transmitting messages.
The information is "sifted" in the most thorough way. In the telegraph, frequently occurring letters, combinations of letters, even whole phrases are depicted with a shorter set of zeros and ones, and those that are less common are shown with a longer one. In the case when the length of the code word is reduced for frequently occurring symbols and increased for rarely occurring ones, one speaks of efficient encoding of information. But in practice, it often happens that the code resulting from the most thorough “sifting”, a convenient and economical code, can distort the message due to interference, which, unfortunately, always happens in communication channels: sound distortion in the phone, atmospheric noise in radio, distortion or darkening of the image in television, transmission errors in the telegraph. These interferences, or, as they are called by experts, noise, fall on the information. And from this there are the most incredible and, of course, unpleasant surprises.
Therefore, to increase the reliability in the transmission and processing of information, it is necessary to introduce extra characters - a kind of protection against distortion. They - these extra characters - do not carry the actual content in the message, they are redundant. From the point of view of information theory, everything that makes a language colorful, flexible, rich in shades, multifaceted, multi-valued, is redundancy. How redundant from such positions is Tatyana's letter to Onegin! How much informational excesses are in it for a short and understandable message "I love you"! And how informationally accurate are the hand-drawn signs that are understandable to anyone and everyone who enters the metro today, where instead of the words and phrases of announcements there are laconic symbolic signs indicating: “Entrance”, “Exit”.
In this regard, it is useful to recall an anecdote told at one time by the famous American scientist Benjamin Franklin about a hatter who invited his friends to discuss a sign project. It was supposed to draw a hat on the sign and write: “John Thompson, the hatter, makes and sells hats for cash” . One of the friends remarked that the words "for cash" are redundant - such a reminder would be offensive to the buyer. Another also found the word "sells" superfluous, since it goes without saying that a hatter sells hats, and does not give them away for free. The third thought that the words "hatter" and "makes hats" were an unnecessary tautology, and the last words were thrown out. The fourth suggested throwing out the word "hatter" - the painted hat clearly says who John Thompson is. Finally, the fifth assured that it was completely indifferent to the buyer whether the hatter was called John Thompson or otherwise, and suggested that this indication be dispensed with. Thus, in the end, there was nothing left on the sign but a hat. Of course, if people used only such codes, without redundancy in messages, then all "information forms" - books, reports, articles - would be extremely short. But they would lose in intelligibility and beauty.
Information can be divided into types according to different criteria: in truth: true and false;
according to the way of perception:
Visual - perceived by the organs of vision;
Auditory - perceived by the organs of hearing;
Tactile - perceived by tactile receptors;
Olfactory - perceived by olfactory receptors;
Taste - perceived by taste buds.
in the form of presentation:
Text - transmitted in the form of symbols intended to designate lexemes of the language;
Numerical - in the form of numbers and signs denoting mathematical operations;
Graphic - in the form of images, objects, graphs;
Sound - oral or in the form of a recording, the transmission of language lexemes by auditory means.
by appointment:
Mass - contains trivial information and operates with a set of concepts understandable to most of the society;
Special - contains a specific set of concepts, when used, information is transmitted that may not be understood by the bulk of society, but is necessary and understandable within a narrow social group where this information is used;
Secret - transmitted to a narrow circle of people and through closed (secure) channels;
Personal (private) - a set of information about a person that determines the social position and types of social interactions within the population.
by value:
Relevant - information is valuable at a given time;
Reliable - information received without distortion;
Understandable - information expressed in a language understandable to the person to whom it is intended;
Complete - information sufficient to make the right decision or understanding;
Useful - the usefulness of information is determined by the subject who received the information, depending on the volume of possibilities for its use.
The value of information in various fields of knowledge
In information theory, many systems, methods, approaches, ideas are being developed nowadays. However, scientists believe that new trends will be added to the modern trends in information theory, new ideas will appear. As proof of the correctness of their assumptions, they cite the “live”, developing nature of science, point out that information theory is surprisingly quickly and firmly introduced into the most diverse areas of human knowledge. Information theory has penetrated into physics, chemistry, biology, medicine, philosophy, linguistics, pedagogy, economics, logic, technical sciences, and aesthetics. According to the experts themselves, the doctrine of information, which arose due to the needs of the theory of communication and cybernetics, stepped over their limits. And now, perhaps, we have the right to talk about information as a scientific concept that puts into the hands of researchers a theoretical and informational method with which you can penetrate into many sciences about animate and inanimate nature, about society, which will allow not only to look at all problems from a new perspective. side, but also to see the unseen. That is why the term "information" has become widespread in our time, becoming part of such concepts as the information system, information culture, even information ethics.
Many scientific disciplines use information theory to emphasize a new direction in the old sciences. This is how, for example, information geography, information economics, and information law arose. But the term "information" has become extremely important in connection with the development of the latest computer technology, the automation of mental work, the development of new means of communication and information processing, and especially with the emergence of computer science. One of the most important tasks of information theory is the study of the nature and properties of information, the creation of methods for its processing, in particular, the transformation of a wide variety of modern information into computer programs, with the help of which the automation of mental work takes place - a kind of strengthening of the intellect, and hence the development of the intellectual resources of society.
The word "information" comes from the Latin word informatio, which means information, clarification, familiarization. The concept of "information" is basic in the course of computer science, but it is impossible to define it through other, more "simple" concepts. The concept of "information" is used in various sciences, and in each science the concept of "information" is associated with different systems of concepts. Information in biology: Biology studies wildlife and the concept of "information" is associated with the appropriate behavior of living organisms. In living organisms, information is transmitted and stored using objects of various physical nature (DNA state), which are considered as signs of biological alphabets. Genetic information is inherited and stored in all cells of living organisms. Philosophical approach: Information is interaction, reflection, cognition. Cybernetic approach: Information is the characteristics of a control signal transmitted over a communication line.
The role of information in philosophy
The traditionalism of the subjective has always dominated in the early definitions of information as categories, concepts, properties of the material world. Information exists outside our consciousness, and can only be reflected in our perception as a result of interaction: reflection, reading, receiving in the form of a signal, stimulus. Information is not material, like all properties of matter. Information stands in the following order: matter, space, time, consistency, function, etc., which are the fundamental concepts of a formalized reflection of objective reality in its distribution and variability, diversity and manifestations. Information is a property of matter and reflects its properties (state or ability to interact) and quantity (measure) through interaction.
From a material point of view, information is the order of the objects of the material world. For example, the order of letters on a sheet of paper according to certain rules is written information. The sequence of multi-colored dots on a sheet of paper according to certain rules is graphic information. The order of musical notes is musical information. The order of genes in DNA is hereditary information. The order of bits in a computer is computer information, and so on. and so on. For the implementation of information exchange, the presence of necessary and sufficient conditions is required.
The necessary conditions:
The presence of at least two different objects of the material or non-material world;
The presence of objects in common property that allows you to identify objects as a carrier of information;
Objects have a specific property that allows them to distinguish objects from each other;
The presence of a space property that allows you to determine the order of objects. For example, the arrangement of written information on paper is a specific property of paper that allows letters to be arranged from left to right and from top to bottom.
There is only one sufficient condition: the presence of a subject capable of recognizing information. This is a person and human society, societies of animals, robots, etc. An informational message is constructed by selecting copies of objects from the basis and arranging these objects in space in a certain order. The length of the informational message is defined as the number of copies of the basis objects and is always expressed as an integer. It is necessary to distinguish between the length of an information message, which is always measured as an integer, and the amount of knowledge contained in an information message, which is measured in an unknown unit of measure. From a mathematical point of view, information is a sequence of integers that are written into a vector. The numbers are the number of the object in the information basis. The vector is called the information invariant, since it does not depend on the physical nature of the basis objects. One and the same informational message can be expressed in letters, words, sentences, files, pictures, notes, songs, video clips, any combination of all previously named.
The role of information in physics
Information is information about the surrounding world (object, process, phenomenon, event), which is the object of transformation (including storage, transmission, etc.) and is used to develop behavior, to make decisions, to manage or to learn.
The characteristics of information are as follows:
This is the most important resource of modern production: it reduces the need for land, labor, capital, reduces the consumption of raw materials and energy. So, for example, having the ability to archive your files (that is, having such information), you can not spend money on buying new floppy disks;
Information brings new productions to life. For example, the invention of the laser beam was the cause of the emergence and development of the production of laser (optical) disks;
Information is a commodity, and the seller of information does not lose it after the sale. So, if a student informs his friend about the schedule of classes during the semester, he will not lose this data for himself;
Information gives additional value to other resources, in particular, labor. Indeed, a worker with a higher education is valued more than a worker with a secondary one.
As follows from the definition, three concepts are always associated with information:
The source of information is that element of the surrounding world (object, process, phenomenon, event), information about which is the object of transformation. So, the source of information that the reader of this textbook is currently receiving is computer science as a sphere of human activity;
The consumer of information is that element of the surrounding world that uses information (for the development of behavior, for decision making, for management or for learning). The consumer of this information is the reader himself;
A signal is a material carrier that captures information for its transfer from a source to a consumer. In this case, the signal is electronic in nature. If the student takes this manual in the library, then the same information will be on paper. Being read and memorized by a student, the information will acquire another carrier - biological, when it is "recorded" in the student's memory.
The signal is the most important element in this circuit. The forms of its presentation, as well as the quantitative and qualitative characteristics of the information contained in it, which are important for the consumer of information, are discussed later in this section of the textbook. The main characteristics of the computer as the main tool that maps the source of information into a signal (link 1 in the figure) and “bringing” the signal to the consumer of information (link 2 in the figure) are given in the Computer section. The structure of the procedures that implement links 1 and 2 and make up the information process is the subject of consideration in the part Information process.
The objects of the material world are in a state of continuous change, which is characterized by the exchange of energy of the object with the environment. A change in the state of one object always leads to a change in the state of some other object in the environment. This phenomenon, regardless of how, which particular states and which particular objects have changed, can be considered as a signal transmission from one object to another. Changing the state of an object when a signal is sent to it is called signal registration.
A signal or a sequence of signals form a message that can be perceived by the recipient in one form or another, as well as in one volume or another. Information in physics is a term that qualitatively generalizes the concepts of "signal" and "message". If signals and messages can be quantified, then we can say that signals and messages are units of measurement of the amount of information. The message (signal) is interpreted differently by different systems. For example, a long and two short beeps in sequence in Morse code terminology is the letter de (or D), in BIOS terminology from AWARD, a video card malfunction.
The role of information in mathematics
In mathematics, information theory (mathematical communication theory) is a section of applied mathematics that defines the concept of information, its properties, and establishes limiting relationships for data transmission systems. The main sections of information theory are source coding (compressive coding) and channel (noise-immune) coding. Mathematics is more than a scientific discipline. It creates a single language for all Science.
The subject of mathematics research is abstract objects: number, function, vector, set, and others. Moreover, most of them are introduced axiomatically (axiom), i.e. without any connection with other concepts and without any definition.
Information is not among the subjects of study of mathematics. However, the word "information" is used in mathematical terms - own information and mutual information, related to the abstract (mathematical) part of information theory. However, in mathematical theory, the concept of "information" is associated with exclusively abstract objects - random variables, while in modern information theory this concept is considered much more widely - as a property of material objects. The connection between these two identical terms is undeniable. It was the mathematical apparatus of random numbers that was used by the author of information theory Claude Shannon. He himself means by the term "information" something fundamental (irreducible). Shannon's theory intuitively assumes that information has content. Information reduces the overall uncertainty and information entropy. The amount of information available to measure. However, he warns researchers against the mechanical transfer of concepts from his theory to other areas of science.
"The search for ways to apply the theory of information in other fields of science is not reduced to a trivial transfer of terms from one field of science to another. This search is carried out in a long process of putting forward new hypotheses and their experimental verification." K. Shannon.
The role of information in cybernetics
The founder of cybernetics, Norbert Wiener, spoke of information as follows:
Information is not matter or energy, information is information. "But the basic definition of information that he gave in several of his books is the following: information is a designation of content that we received from the outside world, in the process of adapting us and our feelings.
Information is the basic concept of cybernetics, just as economic information is the basic concept of economic cybernetics.
There are many definitions of this term, they are complex and contradictory. The reason, obviously, is that various sciences deal with cybernetics as a phenomenon, and cybernetics is only the youngest of them. I. - the subject of study of such sciences as the science of management, mathematical statistics, genetics, the theory of mass media I. (press, radio, television), computer science, which deals with the problems of scientific and technical I., etc. Finally, recently Philosophers show great interest in the problems of reflection: they tend to regard reflection as one of the basic universal properties of matter, connected with the concept of reflection. With all interpretations of the concept of I., it assumes the existence of two objects: the source of I. and the consumer (receiver) of I. The transfer of I. from one to another occurs with the help of signals that, generally speaking, may not have any physical connection with its meaning: this the relationship is determined by agreement. For example, a blow to the veche bell meant that it was necessary to gather in the square, but for those who did not know about this order, he did not inform any I.
In the situation with the vesper bell, the person involved in the agreement on the meaning of the signal knows that at the moment there can be two alternatives: the vespers will take place or not. Or, to put it in the language of I. theory, an indefinite event (veche) has two outcomes. The received signal leads to a decrease in uncertainty: the person now knows that the event (veche) has only one outcome - it will take place. However, if it was known in advance that the veche would take place at such and such an hour, the bell did not announce anything new. It follows from this that the less likely (i.e., more unexpected) the message, the more I. it contains, and vice versa, the more likely the outcome before the event, the less I. contains the signal. Approximately such reasoning led in the 40s. 20th century to the emergence of a statistical, or “classical”, theory of I., which defines the concept of I. through a measure of reducing the uncertainty of knowledge about the accomplishment of an event (such a measure was called entropy). N. Wiener, K. Shannon and Soviet scientists A. N. Kolmogorov, V. A. Kotelnikov and others stood at the origins of this science. ., storage capacity of I. devices, etc., which served as a powerful stimulus for the development of cybernetics as a science and electronic computing technology as a practical application of the achievements of cybernetics.
As for the definition of the value, usefulness of I. for the recipient, there is still a lot of unresolved, unclear. If we proceed from the needs of economic management and, consequently, economic cybernetics, then information can be defined as all the information, knowledge, messages that help solve a particular management problem (that is, reduce the uncertainty of its outcomes). Then some possibilities open up for evaluating I.: it is all the more useful, more valuable, the sooner or at a lower cost it leads to the solution of the problem. The concept of I. is close to the concept of data. However, there is a difference between them: data are signals from which I still need to be extracted. Data processing is the process of bringing them to a form suitable for this.
The process of their transfer from the source to the consumer and perception as I. can be considered as passing through three filters:
Physical, or statistical (a purely quantitative limitation on the bandwidth of the channel, regardless of the content of the data, that is, in terms of syntactic);
Semantic (selection of those data that can be understood by the recipient, i.e., correspond to the thesaurus of his knowledge);
Pragmatic (selection among the understood information of those that are useful for solving a given problem).
This is well shown in the diagram taken from E. G. Yasin's book on economic information. Accordingly, three aspects of the study of I. problems are distinguished - syntactic, semantic, and pragmatic.
According to its content, I. is subdivided into socio-political, socio-economic (including economic I.), scientific and technical, etc. In general, there are many classifications of I., they are built on various grounds. As a rule, due to the proximity of concepts, data classifications are built in the same way. For example, I. is subdivided into static (constant) and dynamic (variable), and data at the same time - into constants and variables. Another division is primary, derivative, output I. (data are classified in the same way). The third division is I. managing and informing. The fourth is redundant, useful and false. Fifth - complete (continuous) and selective. This idea of Wiener gives a direct indication of the objectivity of information, i.e. its existence in nature is independent of human consciousness (perception).
Modern cybernetics defines objective information as an objective property of material objects and phenomena to generate a variety of states that are transferred from one object (process) to another through fundamental interactions of matter and imprinted in its structure. A material system in cybernetics is considered as a set of objects that themselves can be in different states, but the state of each of them is determined by the states of other objects in the system.
In nature, the set of system states is information, the states themselves are the primary code, or source code. Thus, each material system is a source of information. Cybernetics defines subjective (semantic) information as the meaning or content of a message.
The role of information in computer science
The subject of science is precisely the data: methods of their creation, storage, processing and transmission. Content (also: "filling" (in the context), "site content") - a term meaning all types of information (both textual and multimedia - images, audio, video) that make up the content (visualized, for the visitor, content) of the web -site. It is used to separate the concept of information that makes up the internal structure of the page / site (code), from that which will eventually be displayed on the screen.
The word "information" comes from the Latin word informatio, which means information, clarification, familiarization. The concept of "information" is basic in the course of computer science, but it is impossible to define it through other, more "simple" concepts.
The following approaches to the definition of information can be distinguished:
Traditional (ordinary) - used in computer science: Information is information, knowledge, messages about the state of affairs that a person perceives from the outside world with the help of the senses (sight, hearing, taste, smell, touch).
Probabilistic - used in information theory: Information is information about objects and phenomena of the environment, their parameters, properties and state, which reduce the degree of uncertainty and incompleteness of knowledge about them.
Information is stored, transmitted and processed in symbolic (sign) form. The same information can be presented in different forms:
Signed writing, consisting of various signs, among which there is a symbolic one in the form of text, numbers, specials. symbols; graphic; tabular, etc.;
The form of gestures or signals;
Oral verbal form (conversation).
The presentation of information is carried out with the help of languages, as sign systems, which are built on the basis of a certain alphabet and have rules for performing operations on signs. Language is a certain sign system for representing information. Exist:
Natural languages are spoken languages in spoken and written form. In some cases, spoken language can be replaced by the language of facial expressions and gestures, the language of special signs (for example, road signs);
Formal languages are special languages for various areas of human activity, which are characterized by a rigidly fixed alphabet, stricter rules of grammar and syntax. These are the language of music (notes), the language of mathematics (numbers, mathematical signs), number systems, programming languages, etc. At the heart of any language is the alphabet - a set of symbols / signs. The total number of symbols in an alphabet is called the cardinality of the alphabet.
Information carriers are a medium or a physical body for the transmission, storage and reproduction of information. (These are electrical, light, thermal, sound, radio signals, magnetic and laser disks, printed publications, photographs, etc.)
Information processes are processes associated with the receipt, storage, processing and transmission of information (i.e. actions performed with information). Those. These are processes during which the content of information or the form of its presentation changes.
To ensure the information process, a source of information, a communication channel and a consumer of information are needed. The source transmits (sends) information, and the receiver receives (perceives) it. The transmitted information is achieved from the source to the receiver using a signal (code). Changing the signal allows you to get information.
Being an object of transformation and use, information is characterized by the following properties:
Syntax is a property that determines how information is presented on a carrier (in a signal). So, this information is presented on electronic media using a specific font. Here you can also consider such information presentation parameters as the style and color of the font, its size, line spacing, etc. The selection of the required parameters as syntactic properties is obviously determined by the proposed transformation method. For example, for a visually impaired person, the font size and color are essential. If you intend to enter this text into a computer through a scanner, the paper size is important;
Semantics is a property that defines the meaning of information as the correspondence of a signal to the real world. So, the semantics of the signal “computer science” is in the definition given earlier. Semantics can be thought of as some agreement, known to the consumer of information, about what each signal means (the so-called interpretation rule). For example, it is the semantics of signals that is studied by a novice motorist who studies the rules of the road, learning road signs (in this case, the signs themselves act as signals). The semantics of words (signals) is learned by a learner of any foreign language. We can say that the meaning of teaching computer science is to study the semantics of various signals - the essence of the key concepts of this discipline;
Pragmatics is a property that determines the impact of information on consumer behavior. So the pragmatics of the information received by the reader of this study guide is, at least, the successful passing of the computer science exam. I would like to believe that the pragmatics of this work will not be limited to this, and it will serve for further education and professional activity of the reader.
It should be noted that signals of different syntax can have the same semantics. For example, the signals "computer" and "computer" mean an electronic device for converting information. In this case, one usually speaks of signal synonymy. On the other hand, one signal (i.e., information with one syntactic property) can have different pragmatics for consumers and different semantics. Thus, a road sign, known as a “brick” and having a well-defined semantics (“no entry”), means a ban on entry for a motorist, but does not affect a pedestrian in any way. At the same time, the “key” signal can have different semantics: a treble clef, a spring clef, a key to open a lock, a key used in computer science to encode a signal in order to protect it from unauthorized access (in this case, we speak of signal homonymy). There are signals - antonyms that have opposite semantics. For example, "cold" and "hot", "fast" and "slow", etc.
The subject of study of the science of informatics is precisely the data: the methods of their creation, storage, processing and transmission. And the information itself recorded in the data, its meaningful meaning is of interest to users of information systems who are specialists in various sciences and fields of activity: a physician is interested in medical information, a geologist is interested in geological information, an entrepreneur is interested in commercial information, etc. (including a computer scientist who is interested in information on working with data).
Semiotics - the science of information
Information cannot be imagined without its receipt, processing, transmission, etc., that is, outside the framework of information exchange. All acts of information exchange are carried out by means of symbols or signs, with the help of which one system influences another. Therefore, the main science that studies information is semiotics - the science of signs and sign systems in nature and society (the theory of signs). In each act of information exchange, one can find three of its "participants", three elements: a sign, an object that it designates, and a recipient (user) of the sign.
Depending on the relations between which elements are considered, semiotics is divided into three sections: syntactics, semantics and pragmatics. Syntactics studies signs and the relationships between them. At the same time, it abstracts from the content of the sign and from its practical significance for the recipient. Semantics studies the relationship between signs and the objects they designate, while abstracting from the recipient of signs and the value of the latter: for him. It is clear that the study of the patterns of semantic representation of objects in signs is impossible without taking into account and using the general patterns of construction of any sign systems studied by syntactics. Pragmatics studies the relationship between signs and their users. Within the framework of pragmatics, all factors that distinguish one act of information exchange from another, all questions of the practical results of using information and its value for the recipient are studied.
At the same time, many aspects of the relationship of signs between themselves and with the objects they designate are inevitably affected. Thus, the three sections of semiotics correspond to three levels of abstraction (distraction) from the characteristics of specific acts of information exchange. The study of information in all its diversity corresponds to the pragmatic level. Distracting from the recipient of information, excluding him from consideration, we move on to studying it at the semantic level. With a distraction from the content of signs, the analysis of information is transferred to the level of syntactic. Such interpenetration of the main sections of semiotics, associated with different levels of abstraction, can be represented using the scheme "Three sections of semiotics and their relationship." Measurement of information is carried out respectively in three aspects: syntactic, semantic and pragmatic. The need for such a different measurement of information, as will be shown below, is dictated by the practice of designing and organizing the work of information systems. Consider a typical production situation.
At the end of the shift, the site planner prepares data on the implementation of the production schedule. This data is sent to the information and computing center (ICC) of the enterprise, where it is processed, and in the form of reports on the state of production at the current moment, they are issued to managers. Based on the data received, the shop manager decides to change the production plan for the next planning period or to take any other organizational measures. It is obvious that for the head of the shop, the amount of information that the summary contained depends on the magnitude of the economic impact received from its use in decision-making, on how useful the information was. For the site planner, the amount of information in the same message is determined by the accuracy of its correspondence to the actual state of affairs on the site and the degree of surprise of the reported facts. The more unexpected they are, the faster you need to report them to management, the more information in this message. For ITC employees, the number of characters, the length of the message carrying information will be of paramount importance, since it determines the loading time of computer equipment and communication channels. At the same time, neither the usefulness of information, nor the quantitative measure of the semantic value of information is practically of no interest to them.
Naturally, when organizing a production management system, building models for choosing a solution, we will use the usefulness of information as a measure of the information content of messages. When building an accounting and reporting system that provides management of data on the course of the production process, the novelty of the information received should be taken as a measure of the amount of information. The organization of procedures for the mechanical processing of information requires measuring the volume of messages in the form of the number of characters being processed. These three essentially different approaches to measuring information do not contradict or exclude each other. On the contrary, by measuring information on different scales, they allow a more complete and comprehensive assessment of the information content of each message and more efficient organization of the production management system. According to the apt expression of Prof. NOT. Kobrinsky, when it comes to the rational organization of information flows, the quantity, novelty, usefulness of information turn out to be as interconnected as the quantity, quality and cost of products in production.
Information in the material world
Information is one of the general concepts associated with matter. Information exists in any material object in the form of a variety of its states and is transmitted from object to object in the process of their interaction. The existence of information as an objective property of matter logically follows from the well-known fundamental properties of matter - structure, continuous change (movement) and interaction of material objects.
The structure of matter is manifested as an internal dismemberment of integrity, a regular order of connection of elements in the composition of the whole. In other words, any material object, from the subatomic particle of the Meta Universe (Big Bang) as a whole, is a system of interconnected subsystems. As a result of continuous movement, understood in a broad sense as movement in space and development in time, material objects change their states. The state of objects also changes when interacting with other objects. The set of states of the material system and all its subsystems represents information about the system.
Strictly speaking, due to uncertainty, infinity, structural properties, the amount of objective information in any material object is infinite. This information is called complete. However, it is possible to single out structural levels with finite sets of states. Information that exists at a structural level with a finite number of states is called private. For private information, the meaning is the concept of the amount of information.
From the above representation, the choice of the unit of measure for the amount of information follows logically and simply. Imagine a system that can be in only two equally probable states. Let's assign code "1" to one of them, and "0" to the other. This is the minimum amount of information that the system can contain. It is the unit of measurement of information and is called a bit. There are other, more difficult to define, methods and units for measuring the amount of information.
Depending on the material form of the carrier, information can be of two main types - analog and discrete. Analog information changes in time continuously and takes values from a continuum of values. Discrete information changes at some points in time and takes values from a certain set of values. Any material object or process is the primary source of information. All its possible states constitute the code of the source of information. The instantaneous value of states is represented as a symbol ("letter") of this code. In order for information to be transmitted from one object to another as a receiver, it is necessary that there be some kind of intermediate material carrier that interacts with the source. Such carriers in nature, as a rule, are rapidly propagating processes of the wave structure - cosmic, gamma and x-ray radiation, electromagnetic and sound waves, potentials (and maybe not yet discovered waves) of the gravitational field. When electromagnetic radiation interacts with an object, its spectrum changes as a result of absorption or reflection, i.e. the intensities of some wavelengths change. The harmonics of sound vibrations also change during interactions with objects. Information is also transmitted during mechanical interaction, but mechanical interaction, as a rule, leads to large changes in the structure of objects (up to their destruction), and the information is greatly distorted. Distortion of information during its transmission is called misinformation.
The transfer of source information to a carrier structure is called encoding. In this case, the source code is converted into the carrier code. A carrier with a source code transferred to it in the form of a carrier code is called a signal. The signal receiver has its own set of possible states, which is called the receiver code. The signal, interacting with the receiving object, changes its states. The process of converting a signal code into a receiver code is called decoding. The transfer of information from a source to a receiver can be considered as an information exchange. Information interaction is fundamentally different from other interactions. With all other interactions of material objects, there is an exchange of matter and (or) energy. In this case, one of the objects loses matter or energy, while the other receives them. This property of interactions is called symmetry. During information interaction, the receiver receives information, and the source does not lose it. Information interaction is not symmetrical. Objective information itself is not material, it is a property of matter, such as structure, movement, and exists on material carriers in the form of its codes.
Information in wildlife
Wildlife is complex and varied. Sources and receivers of information in it are living organisms and their cells. The organism has a number of properties that distinguish it from inanimate material objects.
Main:
Continuous exchange of matter, energy and information with the environment;
Irritability, the body's ability to perceive and process information about changes in the environment and the internal environment of the body;
Excitability, the ability to respond to the action of stimuli;
Self-organization, manifested as changes in the body to adapt to environmental conditions.
The organism, considered as a system, has a hierarchical structure. This structure, relative to the organism itself, is subdivided into internal levels: molecular, cellular, the level of organs, and, finally, the organism itself. However, the organism also interacts with organismic living systems, the levels of which are the population, the ecosystem, and all living nature as a whole (the biosphere). Not only matter and energy flows, but also information flows between all these levels. Information interactions in living nature occur in the same way as in inanimate nature. At the same time, wildlife in the process of evolution has created a wide variety of sources, carriers and receivers of information.
The reaction to the influences of the external world is manifested in all organisms, since it is due to irritability. In higher organisms, adaptation to the environment is a complex activity that is effective only with sufficiently complete and timely information about the environment. The receivers of information from the external environment are the sense organs, which include sight, hearing, smell, taste, touch and the vestibular apparatus. In the internal structure of organisms, there are numerous internal receptors associated with the nervous system. The nervous system consists of neurons, the processes of which (axons and dendrites) are analogous to information transmission channels. The main organs that store and process information in vertebrates are the spinal cord and brain. In accordance with the characteristics of the sense organs, the information perceived by the body can be classified as visual, auditory, gustatory, olfactory and tactile.
Getting on the retina of the human eye, the signal in a special way excites the cells that make it up. Nerve impulses of cells through axons are transmitted to the brain. The brain remembers this sensation in the form of a certain combination of states of its constituent neurons. (Continuation of the example - in the section "Information in human society"). By accumulating information, the brain creates a connected information model of the surrounding world on its structure. In living nature, for an organism - the receiver of information, an important characteristic is its availability. The amount of information that the human nervous system is able to submit to the brain when reading texts is approximately 1 bit per 1/16 of a second.
The study of organisms is hampered by their complexity. The abstraction of structure as a mathematical set, acceptable for inanimate objects, is hardly acceptable for a living organism, because in order to create a more or less adequate abstract model of an organism, it is necessary to take into account all the hierarchical levels of its structure. Therefore, it is difficult to introduce a measure of the amount of information. It is very difficult to determine the relationships between the components of the structure. If it is known which organ is the source of information, then what is the signal and what is the receiver?
Before the advent of computers, biology, dealing with the study of living organisms, used only qualitative, i.e. descriptive models. In a qualitative model, it is practically impossible to take into account the information links between the components of the structure. Electronic computing technology has made it possible to apply new methods in biological research, in particular, the method of machine modeling, which involves a mathematical description of known phenomena and processes occurring in the body, adding hypotheses about some unknown processes to them, and calculating possible variants of the body's behavior. The resulting options are compared with the actual behavior of the organism, which allows you to determine the truth or falsity of the hypotheses put forward. Information interaction can also be taken into account in such models. Extremely complex are the information processes that ensure the existence of life itself. And although it is intuitively clear that this property is directly related to the formation, storage and transmission of complete information about the structure of the body, an abstract description of this phenomenon seemed impossible for some time. However, the information processes that ensure the existence of this property have been partly revealed through the deciphering of the genetic code and reading the genomes of various organisms.
Information in human society
The development of matter in the process of motion is directed towards the complication of the structure of material objects. One of the most complex structures is the human brain. So far, this is the only structure known to us that has the property that man himself calls consciousness. Speaking about information, we, as thinking beings, a priori mean that information, in addition to its presence in the form of signals we receive, also has some kind of meaning. Forming in his mind a model of the surrounding world as an interconnected set of models of its objects and processes, a person uses semantic concepts, not information. Meaning is the essence of any phenomenon that does not coincide with itself and connects it with a wider context of reality. The word itself directly indicates that the semantic content of information can be formed only by thinking receivers of information. In human society, it is not the information itself that acquires decisive importance, but its semantic content.
Example (continued). Having experienced such a sensation, a person assigns the concept “tomato” to the object, and the concept “red color” to its state. In addition, his consciousness fixes the connection: "tomato" - "red". This is the meaning of the received signal. (Example continued: later in this section). The ability of the brain to create semantic concepts and connections between them is the basis of consciousness. Consciousness can be viewed as a self-developing semantic model of the surrounding world. Meaning is not information. Information exists only on a physical medium. Human consciousness is considered intangible. Meaning exists in the human mind in the form of words, images and sensations. A person can pronounce words not only out loud, but also “to himself”. He can also create (or remember) images and sensations “to himself”. However, he can retrieve the information corresponding to this meaning by speaking or writing the words.
Example (continued). If the words "tomato" and "red color" are the meaning of concepts, then where is the information? Information is contained in the brain in the form of certain states of its neurons. It is also contained in the printed text consisting of these words, and when encoding letters with a three-digit binary code, its number is 120 bits. If you say the words aloud, there will be much more information, but the meaning will remain the same. The greatest amount of information is carried by a visual image. This is reflected even in folklore - "it is better to see once than to hear a hundred times." Information restored in this way is called semantic information, since it encodes the meaning of some primary information (semantics). Hearing (or seeing) a phrase spoken (or written) in a language that a person does not know, he receives information, but cannot determine its meaning. Therefore, in order to transmit the semantic content of information, some agreements are required between the source and the receiver about the semantic content of the signals, i.e. words. Such agreements can be reached through communication. Communication is one of the most important conditions for the existence of human society.
IN modern world information is one of the most important resources and, at the same time, one of the driving forces for the development of human society. Information processes occurring in the material world, wildlife and human society are studied (or at least taken into account) by all scientific disciplines from philosophy to marketing. The increasing complexity of the tasks of scientific research has led to the need to involve large teams of scientists of various specialties in their solution. Therefore, almost all the theories considered below are interdisciplinary. Historically, two complex branches of science - cybernetics and informatics - are directly involved in the study of information.
Modern cybernetics is a multi-disciplinary branch of science that studies super-complex systems, such as:
Human society (social cybernetics);
Economics (economic cybernetics);
Living organism (biological cybernetics);
The human brain and its function - consciousness (artificial intelligence).
Informatics, which was formed as a science in the middle of the last century, separated from cybernetics and is engaged in research in the field of methods for obtaining, storing, transmitting and processing semantic information. Both of these industries use several underlying scientific theories. These include information theory, and its sections - coding theory, algorithm theory and automata theory. Studies of the semantic content of information are based on a complex of scientific theories under the general name of semiotics. Information theory is a complex, mainly mathematical theory, which includes a description and evaluation of methods for extracting, transmitting, storing and classifying information. Considers information carriers as elements of an abstract (mathematical) set, and interactions between carriers as a way of arranging elements in this set. This approach makes it possible to formally describe the code of information, that is, to define an abstract code and explore it with mathematical methods. For these studies, he applies the methods of probability theory, mathematical statistics, linear algebra, game theory and other mathematical theories.
The foundations of this theory were laid by the American scientist E. Hartley in 1928, who determined the measure of the amount of information for some communication problems. Later, the theory was significantly developed by the American scientist C. Shannon, Russian scientists A.N. Kolmogorov, V.M. Glushkov and others. Modern information theory includes both sections coding theory, algorithm theory, digital automata theory (see below) and some others. There are also alternative information theories, for example, "Qualitative information theory", proposed by the Polish scientist M. Mazur. Any person is familiar with the concept of an algorithm, without even knowing it. Here is an example of an informal algorithm: “Cut the tomatoes into circles or slices. Put chopped onion in them, pour over with vegetable oil, then sprinkle with finely chopped capsicum, mix. Before use, sprinkle with salt, put in a salad bowl and garnish with parsley. (Tomato salad).
The first rules for solving arithmetic problems in the history of mankind were developed by one of the famous scientists of antiquity Al-Khwarizmi in the 9th century AD. In his honor, formalized rules for achieving a goal are called algorithms. The subject of the theory of algorithms is to find methods for constructing and evaluating effective (including universal) computational and control algorithms for information processing. To substantiate such methods, the theory of algorithms uses the mathematical apparatus of information theory. The modern scientific concept of algorithms as ways of processing information was introduced in the works of E. Post and A. Turing in the 20s of the twentieth century (Turing Machine). A great contribution to the development of the theory of algorithms was made by Russian scientists A. Markov (Normal Markov Algorithm) and A. Kolmogorov. Automata theory is a section of theoretical cybernetics that studies mathematical models of actually existing or fundamentally possible devices that process discrete information at discrete times.
The concept of an automaton originated in the theory of algorithms. If there are some universal algorithms for solving computational problems, then there must be devices (albeit abstract) for the implementation of such algorithms. Actually, the abstract Turing machine, considered in the theory of algorithms, is at the same time an informally defined automaton. The theoretical justification for the construction of such devices is the subject of automata theory. Automata theory uses the apparatus of mathematical theories - algebra, mathematical logic, combinatorial analysis, graph theory, probability theory, etc. Automata theory, together with the theory of algorithms, is the main theoretical basis for creating electronic computers and automated control systems. Semiotics is a complex of scientific theories that study the properties of sign systems. The most significant results have been achieved in the branch of semiotics - semantics. The subject of research in semantics is the semantic content of information.
A sign system is a system of concrete or abstract objects (signs, words), with each of which a certain value is associated in a certain way. In theory, it is proved that there can be two such comparisons. The first type of correspondence directly defines the material object that denotes this word and is called the denotation (or, in some works, the nominee). The second type of correspondence determines the meaning of the sign (word) and is called the concept. At the same time, such properties of comparisons as “meaning”, “truth”, “definability”, “following”, “interpretation”, etc. are studied. For research, the apparatus of mathematical logic and mathematical linguistics is used. F de Saussure in the 19th century, formulated and developed by C. Pierce (1839-1914), C. Morris (born 1901), R. Carnap (1891-1970) and others. The main achievement of the theory is the creation of a semantic analysis apparatus that allows one to represent the meaning of a text in a natural language as a record in some formalized semantic (semantic) language. Semantic analysis is the basis for creating devices (programs) for machine translation from one natural language to another.
Information is stored by means of its transfer to some material carriers. Semantic information recorded on a material storage medium is called a document. Mankind has learned to store information for a very long time. In the most ancient forms of information storage, the arrangement of objects was used - shells and stones on the sand, knots on a rope. A significant development of these methods was writing - a graphic representation of symbols on stone, clay, papyrus, paper. Of great importance in the development of this direction was the invention of printing. Throughout its history, humanity has accumulated a huge amount of information in libraries, archives, periodicals and other written documents.
At present, the storage of information in the form of sequences of binary characters has gained particular importance. To implement these methods, various storage devices are used. They are the central link of information storage systems. In addition to them, such systems use information retrieval tools (search engine), help obtaining tools (information and reference systems) and information display tools (output device). Formed according to the purpose of information, such information systems form databases, data banks and a knowledge base.
The transfer of semantic information is the process of its spatial transfer from the source to the recipient (addressee). Man learned to transmit and receive information even earlier than to store it. Speech is a method of transmission that our distant ancestors used in direct contact (conversation) - we still use it now. To transmit information over long distances, it is necessary to use much more complex information processes. To implement such a process, information must be formalized (presented) in some way. To represent information, various sign systems are used - sets of predetermined semantic symbols: objects, pictures, written or printed words of a natural language. The semantic information about some object, phenomenon or process presented with their help is called a message.
Obviously, in order to transmit a message over a distance, information must be transferred to some kind of mobile carrier. Carriers can move in space with the help of vehicles, as is the case with letters sent by mail. This method ensures complete reliability of information transmission, since the addressee receives the original message, but requires a significant amount of time for transmission. Since the middle of the 19th century, methods of transmitting information have become widespread, using a naturally propagating carrier of information - electromagnetic oscillations (electrical oscillations, radio waves, light). The implementation of these methods requires:
Preliminary transfer of the information contained in the message to the carrier - encoding;
Ensuring the transmission of the signal thus obtained to the addressee via a special communication channel;
Reverse conversion of the signal code into the message code - decoding.
The use of electromagnetic media makes the delivery of a message to the addressee almost instantaneous, however, it requires additional measures to ensure the quality (reliability and accuracy) of the transmitted information, since real communication channels are subject to natural and artificial interference. Devices that implement the process of data transmission form communication systems. Depending on the method of presenting information, communication systems can be divided into sign (telegraph, telefax), sound (telephone), video and combined systems (television). The most developed communication system in our time is the Internet.
Data processing
Since information is not material, its processing consists in various transformations. Processing processes include any transfer of information from a medium to another medium. The information to be processed is called data. The main type of processing of primary information received by various devices is the transformation into a form that ensures its perception by the human senses. Thus, space photographs obtained in X-rays are converted into ordinary color photographs using special spectrum converters and photographic materials. Night vision devices convert an image obtained in infrared (thermal) rays into an image in the visible range. For some communication and control tasks, it is necessary to convert analog information. For this, analog-to-digital and digital-to-analog signal converters are used.
The most important type of semantic information processing is the determination of the meaning (content) contained in a certain message. Unlike primary semantic information, it does not have statistical characteristics, that is, a quantitative measure - either there is a meaning or it is not. And how much of it, if any, is impossible to establish. The meaning contained in the message is described in an artificial language that reflects the semantic relationships between the words of the source text. A dictionary of such a language, called a thesaurus, resides in the message receiver. The meaning of words and phrases of the message is determined by referring them to certain groups of words or phrases, the meaning of which has already been established. Thesaurus, thus, allows you to establish the meaning of the message and, at the same time, is replenished with new semantic concepts. The described type of information processing is used in information retrieval systems and machine translation systems.
One of the widespread types of information processing is the solution of computational problems and problems of automatic control with the help of computers. Information processing is always done with a purpose. To achieve it, the order of actions on information, leading to a given goal, must be known. This procedure is called an algorithm. In addition to the algorithm itself, you also need some device that implements this algorithm. In scientific theories, such a device is called an automaton. It should be noted as the most important feature of information that, due to the asymmetry of information interaction, new information arises during information processing, and the original information is not lost.
Analog and digital information
Sound is wave vibrations in a medium, such as air. When a person speaks, the vibrations of the throat ligaments are converted into wave vibrations of the air. If we consider sound not as a wave, but as oscillations at one point, then these oscillations can be represented as air pressure changing over time. A microphone can pick up pressure changes and convert them into electrical voltage. There was a transformation of air pressure into electrical voltage fluctuations.
Such a transformation can occur according to various laws, most often the transformation occurs according to a linear law. For example, like this:
U(t)=K(P(t)-P_0),
where U(t) is the electrical voltage, P(t) is the air pressure, P_0 is the mean air pressure and K is the conversion factor.
Both electrical voltage and air pressure are continuous functions in time. The functions U(t) and P(t) are information about the vibrations of the throat ligaments. These functions are continuous and such information is called analog. Music is a special case of sound and it can also be represented as some function of time. It will be an analog representation of music. But music is also recorded in the form of notes. Each note has a duration that is a multiple of a predetermined duration, and a pitch (do, re, mi, fa, sol, etc.). If this data is converted into numbers, then we get a digital representation of music.
Human speech is also a special case of sound. It can also be represented in analog form. But just as music can be broken down into notes, speech can be broken down into letters. If each letter is given its own set of numbers, then we will get a digital representation of speech. The difference between analog information and digital information is that analog information is continuous, while digital information is discrete. The transformation of information from one type to another, depending on the type of transformation, is called differently: simply "conversion", such as digital-to-analog conversion, or analog-to-digital conversion; complex transformations are called "encoding", eg delta coding, entropy coding; the transformation between characteristics such as amplitude, frequency or phase is called "modulation", for example, amplitude-frequency modulation, pulse-width modulation.
Usually, analog conversions are quite simple and can be easily handled by various devices invented by man. A tape recorder converts magnetization on film into sound, a voice recorder converts sound into magnetization on film, a video camera converts light into magnetization on film, an oscilloscope converts electrical voltage or current into an image, and so on. Converting analog information to digital is much more difficult. Some transformations cannot be performed by the machine or can be done with great difficulty. For example, converting speech into text, or converting a concert recording into sheet music, and even by its nature a digital representation: it is very difficult for a machine to convert text on paper into the same text in computer memory.
Why, then, use the digital representation of information, if it is so difficult? The main advantage of digital information over analog is noise immunity. That is, in the process of copying information, digital information is copied as it is, it can be copied almost an infinite number of times, while analog information is noisy during the copying process, its quality deteriorates. Usually, analog information can be copied no more than three times. If you have a two-cassette audio tape recorder, you can make such an experiment, try copying the same song from cassette to cassette several times, after a few such re-recordings you will notice how much recording quality has deteriorated. The information on the cassette is stored in analog form. You can rewrite music in mp3 format as many times as you like, and the quality of the music does not deteriorate. The information in an mp3 file is stored digitally.
Amount of Information
A person or some other receiver of information, having received a portion of information, resolves some uncertainty. Let's take a tree as an example. When we saw the tree, we resolved a number of uncertainties. We learned the height of the tree, the type of tree, the density of the foliage, the color of the leaves, and if it is a fruit tree, then we saw the fruits on it, how ripe they were, etc. Before we looked at the tree, we did not know all this, after we looked at the tree, we resolved the uncertainty - we got information.
If we go out into the meadow and look at it, we will get a different kind of information, how big the meadow is, how tall the grass is, and what color the grass is. If a biologist enters the same meadow, he will, among other things, be able to find out: what varieties of grass grow in the meadow, what type of meadow this is, he will see which flowers have bloomed, which ones will just bloom, whether the meadow is suitable for grazing cows, etc. That is, he will receive more information than we do, since he had more questions before he looked at the meadow, the biologist will resolve more uncertainties.
The greater the uncertainty was resolved in the process of obtaining information, the more information we received. But this is a subjective measure of the amount of information, and we would like to have an objective measure. There is a formula for calculating the amount of information. We have some uncertainty, and we have N-th number of cases of resolution of uncertainty, and each case has some probability of resolution, then the amount of information received can be calculated using the following formula that Shannon suggested to us:
I = -(p_1 \log_(2)p_1 + p_2 \log_(2)p_2 + ... +p_N \log_(2)p_N), where
I is the amount of information;
N is the number of outcomes;
p_1, p_2, ..., p_N - outcome probabilities.
The amount of information is measured in bits - an abbreviation for the English words BInary digiT, which means a binary digit.
For equiprobable events, the formula can be simplified:
I = \log_(2)N, where
I is the amount of information;
N is the number of outcomes.
Take, for example, a coin and throw it on the table. It will land either heads or tails. We have 2 equally likely events. After we tossed a coin, we got \log_(2)2=1 bit of information.
Let's try to find out how much information we get after we roll the die. The cube has six sides - six equally likely events. We get: \log_(2)6 \approx 2.6. After we rolled the die on the table, we got approximately 2.6 bits of information.
The chance of seeing a Martian dinosaur when we leave our house is one in ten in a billion. How much information will we get about the Martian dinosaur after we leave the house?
-\left(((1 \over (10^(10))) \log_2(1 \over (10^(10))) + \left(( 1 - (1 \over (10^(10))) ) \right) \log_2 \left(( 1 - (1 \over (10^(10))) )\right)) \right) \approx 3,4 \cdot 10^(-9) bits.
Suppose we tossed 8 coins. We have 2^8 coin drop options. So after tossing coins we get \log_2(2^8)=8 bits of information.
When we ask a question and are equally likely to get a yes or no answer, then after answering the question we get one bit of information.
Surprisingly, if we apply the Shannon formula for analog information, then we get an infinite amount of information. For example, the voltage at a point in an electrical circuit can take on an equiprobable value from zero to one volt. The number of outcomes we have is infinity, and by substituting this value into the formula for equiprobable events, we get infinity - an infinite amount of information.
Now I'll show you how to encode "War and Peace" with just one notch on any metal rod. Let's encode all the letters and signs found in "War and Peace" using two-digit numbers - they should be enough for us. For example, we will give the letter “A” the code “00”, the letter “B” - the code “01”, and so on, we will encode punctuation marks, Latin letters and numbers. We recode "War and Peace" using this code and get a long number, for example, this is 70123856383901874..., add a comma and zero before this number (0.70123856383901874...). The result is a number from zero to one. Let's put a risk on a metal rod so that the ratio of the left side of the rod to the length of this rod is exactly equal to our number. Thus, if we suddenly want to read War and Peace, we simply measure the left side of the rod to the risks and the length of the entire rod, divide one number by another, get the number and recode it back into letters (“00” to “A”, "01" in "B", etc.).
In reality, we will not be able to do this, since we will not be able to determine the lengths with infinite accuracy. Some engineering problems prevent us from increasing the measurement accuracy, and quantum physics shows us that after a certain limit, quantum laws will already interfere with us. Intuitively, we understand that the lower the measurement accuracy, the less information we receive, and the greater the measurement accuracy, the more information we receive. Shannon's formula is not suitable for measuring the amount of analog information, but there are other methods for this, which are discussed in Information Theory. In computer technology, a bit corresponds to the physical state of the information carrier: magnetized - not magnetized, there is a hole - there is no hole, charged - not charged, reflects light - does not reflect light, high electric potential - low electric potential. In this case, one state is usually denoted by the number 0, and the other by the number 1. Any information can be encoded by a sequence of bits: text, image, sound, etc.
Along with a bit, a value called a byte is often used, usually it is equal to 8 bits. And if the bit allows you to choose one equally likely option out of two possible, then the byte is 1 out of 256 (2 ^ 8). To measure the amount of information, it is also customary to use larger units:
1 KB (one kilobyte) 210 bytes = 1024 bytes
1 MB (one megabyte) 210 KB = 1024 KB
1 GB (one gigabyte) 210 MB = 1024 MB
In reality, the SI prefixes kilo-, mega-, giga- should be used for factors of 10^3, 10^6 and 10^9, respectively, but the practice of using factors with powers of two has historically developed.
A Shannon bit and a computer bit are the same if the probabilities of a zero or one occurring in a computer bit are equal. If the probabilities are not equal, then the amount of information according to Shannon becomes less, we saw this in the example of the Martian dinosaur. The computer amount of information gives an upper estimate of the amount of information. Volatile memory after power is applied to it is usually initialized with some value, for example, all ones or all zeros. It is clear that after power is supplied to the memory, there is no information there, since the values in the memory cells are strictly defined, there is no uncertainty. Memory can store a certain amount of information, but after power is supplied to it, there is no information in it.
Disinformation is deliberately false information provided to an adversary or business partner for more effective conduct of hostilities, cooperation, checking for information leakage and direction of its leakage, identifying potential black market customers. Also, disinformation (also misinformed) is the process of manipulating information itself, such as: misleading someone by providing incomplete information or complete, but no longer necessary information, distorting the context, distorting part of the information.
The purpose of such an impact is always the same - the opponent must act as the manipulator needs. The act of the object against which disinformation is directed may consist in making the decision necessary for the manipulator or in refusing to make a decision that is unfavorable for the manipulator. But in any case, the ultimate goal is the action that will be taken by the opponent.
Disinformation, therefore, is a product of human activity, an attempt to create a false impression and, accordingly, push for desired actions and / or inaction.
Types of disinformation:
Misleading a specific person or group of persons (including an entire nation);
Manipulation (by the actions of one person or a group of persons);
Creating public opinion about some problem or object.
Misrepresentation is nothing more than outright deception, the provision of false information. Manipulation is a method of influence aimed directly at changing the direction of people's activity. There are the following levels of manipulation:
Strengthening the values (ideas, attitudes) that exist in the minds of people that are beneficial to the manipulator;
Partial change of views on a particular event or circumstance;
A radical change in life attitudes.
The creation of public opinion is the formation in society of a certain attitude towards the chosen problem.
Sources and links
en.wikipedia.org - the free encyclopedia Wikipedia
youtube.com - YouTube video hosting
images.yandex.ua - Yandex pictures
google.com.ua - google pictures
en.wikibooks.org - wikibook
inf1.info – Planet of Informatics
old.russ.ru – Russian Journal
shkolo.ru - Information guide
5byte.ru - Informatics website
ssti.ru Information Technology
klgtu.ru - Informatics
informatika.sch880.ru - website of the computer science teacher O.V. Podvintseva
bibliofond.ru - electronic library Bibliofond
life-prog.ru - programming
The main difference between data and information is that data is the source material for processing, while information is the product of processing, its result.
Data
Data is the original unorganized materials or facts that, after processing, become information. The data itself is useless until it is processed or used for something else. Data has no meaning until it is interpreted.
Data examples
- Citizens data: During correspondence, data on all citizens of the state is collected and updated.
- Poll data: Various companies collect survey data in order to find out people's opinions about their products.
- Exam data: The exams collect data on the scores of all examinees.
Information
Information is processed data. Data that can be useful is called information. Information is data plus its meaning. Data does not depend on information, but information depends on data; it cannot be obtained without the help of data. Information is the meaning obtained by assembling data.
Information examples
- Census report: Population census data is used to compile reports/gather the necessary information in general about the population of the country, the level of education, etc.
- Survey reports and survey results: Survey data is summarized into reports/required information required by company management.
- Exam results for each student: During the exam, the system collects data (student grades for each subject) and processes the collected data.
Key differences
- Data is the language for receiving data for a computer, and information is a language for outputting computer data that is understandable to humans.
- Data is raw facts and figures, while information is processed data that has become meaningful.
- Data does not depend on information, but information depends on data; without data, information cannot be obtained.
- The data is not specific, the information must be specific enough to make sense.
In communication theory, a message is a statement, text, image, physical object, or action intended to be conveyed. Messages consist of verbal or non-verbal cues. A single signal cannot contain much information, so a series of successive signals is used to transmit information. The sequence of signals is called a message.
Thus, information is transmitted from the source to the receiver in the form of messages. The message acts as a material shell for the presentation of information during transmission. Therefore, the message serves as a carrier of information, and the information is the content of the message.
The relationship between a message and the information it contains is called message interpretation rule. This correspondence can be unambiguous And ambiguous. In the first case, the message has only one interpretation rule. In the second case, the correspondence between a message and information is possible in two ways: the same information can be transmitted by different messages (for example, news can be received by radio, from a newspaper, by telephone, etc.); the same message may contain different information for different receivers (for example, a fall in the stock price on the stock exchange is a catastrophe for some, an opportunity for enrichment for others).
Since the sequence of signals is a message, the quality of discontinuity-continuity of signals is transferred to the message. There are concepts of continuous (analogue), discrete, quantized and digital messages.
Note that information does not have this quality, since information is an intangible category and cannot have the property of discreteness or continuity, although the same information can be presented through various messages, including signals that differ in nature.
In computer science, combinations of continuous and discrete information are sometimes used. They come from abbreviations of full phrases: information presented by means of continuous signals, And information represented by discrete signals. Therefore, when it comes to the types of information, it is more correct to talk about the forms of its presentation in the message, or about the types of messages.
When forming a message, along with the signal, concepts such as a sign, a letter and a symbol are also used. Let's look at the differences between them.
Sign is an element of some finite set of distinct entities.
The nature of the sign can be any - a gesture, a drawing, a letter, a traffic signal, a sound, and is determined both by the carrier of the message and the form of presentation of information in the message. The whole set of characters used to represent discrete information is called a set of signs. A set is a discrete set of characters.
The set of characters in which their order is set is called the alphabet. Alphabet is an ordered collection of signs. The order of characters in the alphabet is called lexicographic and provides an opportunity to establish relationships more less: for two G signs< Д, если порядковый номер у Г в алфавите меньше, чем у Д.
The characters used to represent the phonemes of human language are called letters, and their totality language alphabet.
By themselves, a sign or a letter does not carry any semantic content. However, such content can be attributed to them - in this case, the sign will be called symbol. For example, stress in physics is usually denoted by the letter u, hence, U in formulas is a symbol of the physical quantity "voltage". Another example of symbols would be pictograms representing in computer programs objects or actions.
Thus, the concepts of "sign", "letter" and "symbol" cannot be considered identical, although very often there is no distinction between them, therefore in computer science there are concepts of "character variable", "encoding of alphabetic characters", "symbolic information". In all the examples given, instead of the term "character" it would be more correct to use "sign" or "letter".
It seems important to emphasize once again that the concepts of a sign and an alphabet can only be attributed to discrete messages.
To store information, a person primarily uses his memory. The brain is one of the most advanced stores of information, in many ways superior to computer tools.
Unfortunately, people forget a lot. In addition, it is necessary to transfer knowledge to other people, including the next generations. Therefore, in ancient times, people recorded information on stone, papyrus, birch bark, parchment, and then on paper. In the 20th century, new means of information storage appeared: punched cards and punched tapes, magnetic tapes and magnetic disks, laser disks, flash memory.
In any case, the information is stored on some carrier, which has "memory", that is, it can be in different states. The carrier passes from one state to another under some external influence, and without influences it retains its state.
When information is recorded, the properties of the medium change: text and drawings are applied to paper; individual sections are magnetized on magnetic disks and tapes; On laser disks, regions are formed that reflect light in different ways. Thus, information is also encoded for storage.
| The information is stored in an encrypted form. |
During storage, the properties of the media remain unchanged, which makes it possible to read the recorded information later. Note that the processes of writing and reading are processes of information transfer.
1. Who (what) can be the source (receiver) of information? Give examples.
2. What is a signal? Give examples of signals.
3. What is a message? How is receiving information different from receiving a message?
4. Give examples when receiving a message does not mean receiving information.
5. Give examples when the same information can be transmitted using different messages.
6. Give examples when the same message carries different information for different people.
7. Tell us how interference affects the transmission of information. Give examples.
8. What is redundancy? Why is it useful in conveying information?
9. Imagine that you came up with a language in which there is no redundancy. What will be its disadvantage?
10. What do you think, which version of the Russian language has the most redundancy: colloquial, literary, legal, the language of air traffic controllers? Why?
11. What types of information processing do you know?
12. Under what types of information processing does its content change?
13. Under what types of information processing only the form of its presentation changes?
14. What type of processing is encryption? Why?
15. Employees of a remote weather station measure the temperature and humidity of the air every 3 hours, and transmit the data via radio to the regional meteorological center. There, these data are summarized in a table and sent by e-mail to the hydrometeorological center, where powerful computers make a weather forecast. Highlight here the processes associated with the processing, transmission and reception of information.
16. Vasya found information about the population of Moscow in the 19th century in an old book, compiled a table based on this data, built a diagram and made a report at a school conference. Highlight here the processes associated with the processing and transmission of information.
17. Why does a person write down information?
18. What are the advantages and disadvantages of human memory in comparison with computer?
19. In what tasks can a computer not compete with a person? Why? In what situations is a person clearly inferior to a computer?
20. What means of information storage are used in computer technology? Which of them are already out of use or out of use? Why?
