The word "information" is "information" in English, French, German, and Spanish, and "intelligence" in Japanese. It first appeared as a scientific term in the article "Information Transmission" written by R.V. Hartley in 1928. In the 40s of the 20th century, C.E. Shannon, the founder of information, gave a clear definition of information, and since then, many researchers have given different definitions from their respective research fields. The representative expressions are as follows:

Shannon, the founder of information, believes that "information is something that is used to eliminate random uncertainty", and this definition is regarded as a classic definition and is cited.

Norbert Wiener, the founder of cybernetics, believed that "information is the content and name that people exchange with the external world in the process of adapting to the external world and making this adaptation react on the external world", which is also cited as a classical definition.

Economic management scholars believe that "information is effective data to provide decision-making".

Scientific terminology

Josiah Willard Gibbs, a famous American physical chemist, founded vector analysis and introduced it into mathematical physics, which made the study of uncertainty and chance of events find a new angle, so that human beings can make a difference in science

Information

Information (5 photos)

The first step is taken in learning to grasp the meaning of information. He argues that "entropy" is a measure of the lack of information about a physical system.

Electronics scientists and computer scientists believe that "information is a signal transmitted in an electronic circuit".

Professor Zhong Yixin, a well-known informatics expert in China, believes that "information is the way of existence or the state of motion of things, and the direct or indirect expression of this way or state".

F.W. Horton, an American information management expert, defines information as: "Information is data that has been processed to meet the needs of user decision-making." "Simply put, information is processed data, or rather, information is the result of data processing.

Based on the results of research on information. The scientific concept of information can be summarized as follows:

Information is a reflection of the state of motion and changes of various things in the objective world, a representation of the interconnection and interaction between objective things, and a manifestation of the essence of the state of motion and changes of objective things.

deliver

Ancient

By word of mouth or with the help of utensils

The speed of information transmission is slow and impreciseAntiquity

Rely on the post to travel long distances

The speed of information transmission is slow and the form of information is single.

Modern

A postal system that relies on means of transport

The speed of information transmission is relatively fast, the distance is relatively slow, and the cost is high.

nowadays

Telegraph, telephone

Fast speed, single text information.

Contemporary

network

The amount of information transmitted is large, the information is diverse, and the transmission speed is extremely fast and not hindered by geography.

function

It reflects the internal attributes, state, structure, interconnectedness and interaction with the external environment of things, and reduces the uncertainty of things.

Information Features Edited

Don't worry, information is uncertain, but there are ways to quantify it. According to the concept of information, people can summarize that information has the following characteristics:

1. The greater the probability of the occurrence of message x, the greater the amount of information, and conversely, the smaller the probability of occurrence, the greater the amount of information. It can be seen that the amount of information (which we denote as I) and the probability of a message occurring are inversely related.

2. When the probability is 1, 100% of what happens is known to everyone on the earth, so the amount of information is 0.

3. When a message is composed of multiple independent messages, the amount of information contained in the message should be equal to the sum of the information contained in each message.

According to these characteristics, if it is expressed mathematically as a logarithmic function, it can be expressed as the relationship between the amount of information and the probability of the occurrence of the message: I=-loga(P(x)). Since information can be quantified, then it must be given a unit, right? A person's weight is measured in kilograms, and a person's height is measured in meters, so what unit should the amount of information be measured? Usually the amount of information is measured in bits, which is more convenient, because the amount of information in a binary waveform is exactly equal to one bit.

Info & Bit Editing

Some students have another question: So my home Internet speed of 2Mbit/s means that the amount of information can be transmitted 2Mbit per second?

Bits here do not strictly refer to the amount of information, but to the signal. Originally, it could not be said to be a signal of several bits, but because the amount of information of a binary waveform (symbol) is exactly equal to 1 bit, in engineering applications, a binary code element is often called 1 bit, and the information unit becomes a signal unit. This is not rigorous, but it is not contradictory. Let's just pay attention to the conceptual distinction.

Some students still have questions: Suppose there is a message "wolf" and it is converted into a 100-bit data packet through source encoding, then the amount of information is 100 bits. Then the 100 bits were sent to a lot of people through the communication network, and many people received 100 bits of information. However, some people think that the news of "the wolf is coming" is very important and very informative, but some people feel that it does not matter and has very little information. But we know that the amount of information in this message is 100 bits, why is it different?

First of all, as we just said, bits are a unit of information, but it is also customary for engineering to use it as a unit of signal. The 100-bit here refers to the signal. Secondly, the basic problem in communication is to reproduce information from one point to another, which refers to a point-to-point situation. But even in the case of point-to-multipoint, because in the actual communication system, the message tends to refer to some symbol that is sent. The amount of information that these symbols can carry is related to the probability of the occurrence of these symbols, and for any receiver, the probability of the occurrence of these symbols is certain, and it will not be said that it is this probability for this receiver and that probability for that receiver. For example, if there is a string of symbols, 221234 this string of symbols is composed of four symbols: 1, 2, 3, and 4, assuming that the probability of the occurrence of the four symbols is 1/4, then in this string of symbols, 2 appears 3 times, so the amount of information carried by 2 is -3×log2(1/4)=6bit. We need to understand that the symbols transmitted in the communication system are equivalent to the messages we are talking about now?

Word Concept Editing

Basic explanation

[Information]: A signal purposefully marked on the input of a communication system or computer... (e.g. a digit of a phone number)

[Message]: Voice message related sentence: I heard that Zhihua asked to see, it must be that the husband has information, so he hurriedly invited in. - "Three Heroes and Five Righteousness" [1]

Cited explanations

1. Messaging.

Southern Tang Dynasty Li Zhong's poem "Nostalgia for the Old Man in Late Spring": "Dreaming of beauty and sinking information, eyes through the long road and leaning on the tower." Song Chenliang's poem "Plum Blossoms": "If you want to spread the message of spring, you are not afraid of being buried in the snow." "The fourth and fourth chapter of "Water Margin": "Song Jiang was overjoyed and said: "Only the virtuous brother goes quickly, and he will know the information in ten days." Ba Jin's "Home" Trinity: "What's going on with my second cousin? Why didn't you even give me a message?"

2. Modern science refers to the content contained in messages, instructions, data, symbols, etc., sent by things. Man is able to understand and transform the world by obtaining and recognizing different information about the natural world and society to distinguish different things. In all communication and control systems, information is a form of universal connection.

Chen Yuan, Sociolinguistics, 4.1: "According to the concept of physics, information is nothing more than a sequence of signals arranged in a certain way. In social communication, this definition is not enough: the information must also have a certain meaning, or the information must be the 'carrier of meaning'. Science Illustrated, No. 1, 1983: "The operation of the entire subway is controlled by a central electronic computer, and the information it relies on comes from the highly sensitive instruments installed in and between stations. ” [1]

Glossary More Brochures

Entry image

Entry Image(1)

Information

Information (5)

Principles and basic techniques of communication

▪ ▪ Communications, Telecommunications ▪, Information ▪ Technology, Analog ▪ Communications

▪ Jeep curve ▪, digital communication ▪, wired communication ▪, radio communication ▪, wireless communication

▪ Telephone communication ▪, data communication ▪, image communication ▪, still image communication ▪, full activity video

▪ Fax Communication ▪, Fax Store-and-Forward ▪, Video Communication ▪, Multimedia Communication ▪, Adaptive[of]

▪ Adaptive communication ▪ network [network] ▪ hierarchical network [network] ▪ peer-to-peer network ▪ active network

▪ Passive network ▪ Network topology ▪ Star network ▪ Tree network ▪ Mesh network

▪ Ring network ▪, overlapping network ▪, communication system, ▪ time-varying system ▪, source

▪ Anchor ▪ Channel ▪ Channel ▪ Channel ▪ Physical Channel

Other technical terms

Resources

1. Reference: Handian[Citation date: 2013-11-12]

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1 Definitions of Terms

1.1 Scientific Terminology

1.2 Passing

1.3 Features

2 Information characteristics

3 Messages & Bits

4 Word Concepts

4.1 Basic Explanations

4.2 Citations

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