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Two different values are encoded using two bits: 00, 01, 10, 11

Two different values are encoded using two bits: 00, 01, 10, 11Two different values are encoded using two bits: 00, 01, 10, 11. Three states can be used to encode 8 states: 000 001 010 011 100 101 110 111 In general, 2n states can be encoded using n bits. The information transfer rate is measured by the number of bits transmitted in one second. The bit rate in one second is called 1 Baud. Derived units of the transmission speed are called Kbaud, Mbaud and Gbaud: 1 Kbaud (one kilobod) = 2 10 baud = 1024 bits / s; 1 Mbaud (one megabaud) = 2 20 baud = 1024 Kbps; 1 Gbps (one gigabyte) = 2 30 baud = 1024 Mbps. Example. Let the modem transmit information at a speed of 2400 baud. To transmit one character of the text you need to transfer about 10 bits. Thus, the modem can transmit about 2400/10 = 240 characters in 1 second. On a computer, you can process not only numbers, but also texts. In this case, you need to encode about 200 different characters. In binary, this requires at least 8 bits (28 = 256). This is enough to encode all the characters of the English and Russian alphabets (lowercase and uppercase), punctuation, symbols of arithmetic operations of some generally accepted special characters. There are currently several coding systems. The most common are the following coding systems: ASCII, Windows-1251, KOI8, ISO.

ASCII (American Standard Code for Information Interchange) ASCII system has 2 coding tables: basic and advanced. The base table fixes the values of the codes from 0 to 127, extended from 128 to 255. The first 32 codes (0-31) contain the so-called control codes that do not correspond to any language characters, and, accordingly, the codes are not displayed on the screen or on print device. Starting from code 32 to code 127, the English character codes are placed. The characters of the national alphabet are placed in codes from 128 to 255. Encoding Windows-1251 has become the standard in the Russian sector of the Wold Wide Web. KOI8 (information exchange code) is the standard encoding in e-mail messages and newsgroups. ISO (International Standard Organization) - an international standard. This encoding is rarely used. The advent of computer science is due to the emergence and dissemination of a new technology for the collection, processing and transmission of information related to the recording of data on computer media. The main computer science tool is a computer. The computer, which got its name from its original purpose - performing calculations, has a second very important application. He became the indispensable assistant of man in his intellectual activity and the main technical means of information technology. And the rapid development in recent years of the technical and software capabilities of personal computers, the spread of new types of information technologies create real opportunities for their use, opening up qualitatively new ways for the user to further develop and adapt to the needs of society. Disinformation Disinformation is deliberately false, false information provided to an opponent or enemy in order to conduct military operations more effectively, to obtain any competitive advantages, to check for information leakage and to identify the source of leakage, to identify potentially unreliable clients or partners. Also, the process of manipulating information is called disinformation, such as misleading someone by providing incomplete information or complete, but no longer relevant information, distorting the context, distorting any part of the information. Disinformation, as we see, is the result of human activity, the desire to create a false impression and, accordingly, to push to the required actions and / or inaction - Source: The concept of information. Informatics

Types of information Information can exist in various forms: text, drawings, drawings, photographs; light or sound signals; radio waves; electrical and nerve impulses; magnetic recordings; gestures and facial expressions; smells and tastes; chromosomes through which the signs and properties of organisms are transmitted by inheritance, etc. There are main types of information that are classified by its presentation form, its encoding and storage methods: graphic - one of the oldest types with which information about the world was stored in the form of cave paintings, and then in the form of paintings, photographs, diagrams, drawings on various materials (paper, canvas, marble, etc.) that depict paintings of the real world; sound (acoustic) - a sound recording device was invented to store sound information in 1877, and for music information - a coding method using special characters was developed that makes it possible to store it as graphic information; textual - encodes a person’s speech with the help of special characters - letters (for each nation its own); paper is used for storage (notes in notebooks, typography, etc.); numerical - encodes a quantitative measure of objects and their properties in the environment using special characters - numbers (for each coding system its own); became especially important with the development of trade, the economy and money exchange; video information is a way of storing “live” pictures of the world that appeared with the invention of cinema. There are also types of information for which encoding and storage methods have not yet been invented — tactile information, organoleptic information, etc. Initially, information was transmitted over long distances using coded light signals, after the invention of electricity — transmission of a signal encoded in a certain way over wires, and later — using radio waves. . Remark 1 Claude Shannon, who also laid the foundation for digital communication, wrote the book “Mathematical Communication Theory” in 1948, in which he first substantiated the possibility of using binary code for transmitting information. The first computers were a means of processing numerical information. With the development of computer technology, PCs began to be used for storing, processing, transmitting various types of information (text, numerical, graphic, sound and video information). Information can be stored using a PC on magnetic disks or tapes, on laser disks (CD and DVD), special non-volatile memory devices (flash memory, etc.). These methods are constantly being improved, and information carriers are invented. All actions with information are performed by the central processor of the PC. Objects, processes, phenomena of the material or non-material world, if viewed from the point of view of their informational properties, are called informational objects. A lot of different information processes can be performed on information, including: creation; reception; combination; storage; broadcast; copying; treatment; Search; perception; formalization; division into parts; measurement; using; Spread; simplification; destruction; memorization; transformation; collection, etc. Information properties Information, like any object, has properties, the most important of which, from the point of view of computer science, are: Objectivity. Objective information - existing independently of human consciousness, methods of fixing it, someone else's opinion or attitude. Credibility. Information reflecting the true state of affairs is reliable. Inaccurate information most often leads to misunderstanding or wrong decisions. Obsolescence of information can make unreliable information from reliable information, as it will no longer be a reflection of the true state of affairs. Completeness. Information is complete if it is sufficient for understanding and decision making. Incomplete or redundant information may lead to a delay in decision-making or an error. The accuracy of information is the degree of its proximity to the real state of an object, process, phenomenon, etc. The value of information depends on its importance for decision making, problem solving, and further applicability in any type of human activity. Relevance. Only the timely receipt of information can lead to the expected result. Clearness. If it is unclear to express valuable and timely information, then it will most likely become useless. Information will be understandable when it is at least expressed in a language that is understandable to the recipient. Availability. The information should correspond to the level of perception of the recipient. For example, the same questions are stated differently in textbooks for schools and universities. Brevity. Information is perceived much better if it is not presented in detail and verbose, but with an acceptable degree of compression, without unnecessary details. The brevity of information is indispensable in reference books, encyclopedias, instructions. Logical, compact, comfortable

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