The birth of the first computer

The first computer (ENIAC) was born in the United States in February 1946.

ENIAC PC

Cost1100,000 USD, 600 USD

Weight: 30 tons 10kg

Covering area 150 m2 0.25m2.

Electronic devices 19000 electron tubes 100 integrated circuits.

The operation speed is 5000 times/second and 5 million times/second.

Second, the history of computer development

1, the first generation computer (1946~ 1958)

Electron tube is the basic electronic device; Use machine language and assembly language; Mainly used for national defense and scientific calculation; The operation speed ranges from thousands to tens of thousands of times per second.

2. The second generation computer (1958~ 1964)

Transistor is the main device; The operating system and algorithm language appeared on the software; The operation speed ranges from tens of thousands to hundreds of thousands of times per second.

3. Third generation computers (1964~ 197 1)

Integrated circuits are widely used; The volume of transactions has shrunk; The operation speed ranges from hundreds of thousands to millions of times per second.

4. Fourth generation computers (197 1~)

Large-scale integrated circuit is the main device; The operation speed ranges from one million times per second to hundreds of millions of times.

Third, the history of computer development in China

Starting from 1953, the first computer in China was developed.

1982, China developed the first and second series computers of Yinhe, with the operation speed of 1 100 million times.

The history of computers

Computer is the main force of the new technological revolution, and it is also a positive factor to promote the modernization of society. Computer science and technology is one of the fastest developing and most far-reaching emerging disciplines since the Second World War. Worldwide, the computer industry has developed into a strategic industry with strong vitality.

Modern computer is a general tool for automatically processing information according to programs. Its processing object is information, and the processing result is also information. Using computers to solve various problems such as scientific calculation, engineering design, management, process control or artificial intelligence are all carried out according to certain algorithms. This algorithm is a series of well-defined rules, pointing out how to generate the required output information with given input information through limited steps.

The general process of information processing is that computer users pre-program the problems to be solved and store them in the computer, and then use the stored programs to command and control the computer to automatically carry out various basic operations until the expected processing results are obtained. The basis of computer automatic work lies in this way of storing programs, and its universality lies in the * * * method of using computers to process information.

The history of computers

The birth and development of modern computer Before the appearance of modern computer, the development of computer experienced three stages: mechanical computer, electromechanical computer and budding electronic computer.

As early as the17th century, a group of mathematicians in Europe began to design and manufacture digital computers to perform basic operations in digital form. 1642, the French mathematician Pascal made the earliest decimal adder by using a gear transmission device similar to a clock. 1678, the computer made by German mathematician Leibniz further solved the multiplication of decimal numbers and Divison.

Babbage, a British mathematician, put forward an idea when he made the differential extension model in 1822. Every time an arithmetic operation is completed, it will develop into an automatic completion of a specific complete operation process. 1884, Babbage designed a program-controlled universal analyzer. Although this analyzer has described the prototype of the computer related to the program control mode, it has not been realized due to the technical conditions at that time.

In the more than 100 years since Babbage's idea was put forward, great progress has been made in electromagnetism, electrotechnics and electronics, and vacuum diodes and vacuum triodes have been invented one after another in components. In terms of system technology, wireless telegraph, television and radar were invented one after another. All these achievements have prepared technical and material conditions for the development of modern computers.

At the same time, mathematics and physics have flourished accordingly. By 1930s, all fields of physics were going through the stage of quantification, and mathematical equations described various physical processes, some of which were difficult to be solved by classical analytical methods. Therefore, numerical analysis is valued, and numerical solutions of various numerical integrals, numerical differentials and differential equations are developed, which simplifies the calculation process into a huge amount of basic operations, thus laying the foundation for numerical algorithms of modern computers.

The urgent need for advanced computing tools in society is the fundamental driving force for the birth of modern computers. Since the 20th century, numerous computational difficulties have appeared in various scientific fields and technical departments, which have hindered the continuous development of disciplines. Especially before and after the outbreak of World War II, the demand for high-speed computing tools in military science and technology is particularly urgent. During this period, Germany, the United States and Britain were all developing computers, and almost at the same time began to study electromechanical computers and electronic computers.

Giuseppe, a German, was the first person to make a computer with electronic components. The fully automatic relay computer Z-3, which he made in 194 1 year, has the characteristics of modern computers such as floating-point counting, binary operation and digital storage address instruction. In the United States, relay computers include MARK- 1, MARK-2, Model- 1, Model-5, etc. It was also done during 1940 ~ 1947. But the switching speed of relay is about one hundredth of a second, which greatly limits the operation speed of computer.

The development of electronic computer has experienced the evolution from making parts to the whole machine, from special machine to general machine, from "external program" to "stored program" 1938, atanasoff, a Bulgarian-American scholar, first made the computing parts of electronic computer. 1943, a "giant" electronic computer was built by the Communication Office of the British Foreign Office. This is a special cryptanalysis machine, which was used in World War II.

1946 In February, the large electronic digital integral computer (ENIAC) manufactured by Moore College of the University of Pennsylvania in the United States was originally used for artillery trajectory calculation. After many improvements, it became a general-purpose computer, which can perform various scientific calculations. This computer, which completely uses electronic circuits for arithmetic operation, logical operation and information storage, is 1000 times faster than the relay computer. This is the world's first electronic computer that people often mention. However, the program of this computer is still external, and the storage capacity is too small, which has not fully possessed the main characteristics of modern computers.

This new breakthrough was achieved by a design team led by mathematician von Neumann. 1in March, 945, they published a brand-new general-purpose electronic computer program-Electronic Discrete Variable Automata (EDVAC). Subsequently, in June of 1946, von Neumann and others put forward a more perfect design report and made a preliminary study on the logical structure of electronic computer equipment. From July to August of the same year, they taught a special course "Computer Design Theory and Technology" to experts from more than 20 institutions in the United States and Britain at Moore College, which promoted the design and manufacture of stored program computers.

1949, the mathematics laboratory of Cambridge University in England took the lead in making the electronic discrete-time automatic computer (EDSAC). The United States made the Oriental Standard Automatic Computer (SFAC) 1950. At this point, the embryonic period of electronic computer development ended and the development period of modern computer began.

While creating digital computer, another important computing tool-analog computer has also been developed. When physicists summarize the laws of nature, they often use mathematical equations to describe a process. On the contrary, physical process simulation can also be used to solve mathematical equations. After the invention of logarithm, the slide rule made by 1620 has changed the multiplication and division method into addition and subtraction method for calculation. Maxwell skillfully transformed the calculation of integral (area) into the measurement of length and made an integrator in 1855.

Fourier analysis is another great achievement of mathematical physics in the19th century, which has directly promoted the development of the simulator. 1At the end of the 9th century and the beginning of the 20th century, 65438+ manufactured various resolvers for calculating Fourier coefficients and differential resolvers for solving differential equations. However, when trying to popularize differential analyzer to solve partial differential equations and simulator to solve general scientific calculation problems, people gradually realize the limitations of simulator in universality and accuracy, and turn their main energy to digital computers.

After the emergence of electronic digital computers, analog computers continued to develop and combined with digital computers to produce hybrid computers. Simulators and mixers have developed into special varieties of modern computers, namely, efficient information processing tools or simulation tools in specific fields.

Since the mid-20th century, computers have been in a period of rapid development, from hardware only to computer systems including hardware, software and firmware. The performance-price ratio of computer system is two orders of magnitude higher than that of every 10 year on average. The types of computers have been divided again and again, and developed into microcomputers, minicomputers, general-purpose computers (including giant, large and medium-sized computers) and various special-purpose computers (such as various control computers and analog-digital mixed computers).

Computer equipment, from electron tubes to transistors, from discrete components to integrated circuits to microprocessors, has made three leaps in the development of computers.

In the era of electron tube computer (1946 ~ 1959), computers were mainly used for scientific calculation. Main memory is the main factor that determines the appearance of computer technology. At that time, the main memories were mercury delay line memory, cathode ray oscilloscope electrostatic memory, magnetic drum and magnetic core memory, and computers were usually classified according to this.

In the era of transistor computer (1959 ~ 1964), the core memory was used as the main memory, and the drum and disk began to be used as the main and auxiliary memories. Not only are scientific computing computers developing, but small and medium-sized computers, especially cheap small data processing computers, are also being mass-produced.

1964 with the development of integrated circuit computers, computers have also entered the development period of product serialization. Semiconductor memory has gradually replaced the main memory position of core memory, and disk has become an indispensable auxiliary memory. Virtual storage technology has been widely used. With the rapid development of various semiconductor read-only memories and rewritable read-only memories, as well as the development and application of microprogramming technology, firmware subsystems began to appear in computer systems.

After the 1970s, the integration of integrated circuits for computers developed rapidly from small scale to large scale and super-large scale, and microprocessors and microcomputers came into being, and the performance of various computers improved rapidly. With the appearance and wide application of microcomputers with word lengths of 4-bit, 8-bit, 16-bit, 32-bit and 64-bit, the demand for minicomputers, general-purpose computers and special-purpose computers has increased accordingly.

After microcomputers are widely used in society, there are often dozens or even hundreds of computers in an office building, a school and a warehouse. The local area network (LAN) to realize their interconnection rose immediately, which further promoted the development of computer application system from centralized system to distributed system.

In the era of electron tube computer, some computers were equipped with assembly language and subroutine library, and FORTRAN, a high-level language for scientific calculation, appeared. In the stage of transistor computer, advanced languages such as COBOL language for transaction processing, ALGOL language for scientific computer and LISP language for symbol processing began to enter the practical stage. The initial formation of the operating system has changed the use of computers from manual operation to automatic job management.

After entering the development period of integrated circuit computer, a considerable scale software subsystem has been formed in the computer, the types of high-level languages have been further increased, and the operating system has been improved day by day, with many functions such as batch processing, time-sharing processing and real-time processing. The software subsystem also adds database management system, communication processing program and network software. The function of the software subsystem is constantly enhanced, which obviously changes the use attribute of the computer and significantly improves the use efficiency.

In modern computers, the value of peripheral equipment has generally exceeded half of the computer hardware subsystem, and its technical level largely determines the technical appearance of computers. The technology of peripheral equipment is very comprehensive, which depends not only on the integration of electronics, machinery, optics, magnetism and other disciplines, but also on precision machinery technology, electrical and electronic processing technology, measurement technology and technology level.

Peripheral devices include auxiliary memory and input and output devices. Auxiliary memory includes magnetic disk, magnetic drum, magnetic tape, laser memory, mass memory and micro memory. Input and output devices are divided into input, output, conversion, mode information processing devices and terminal devices. Among these devices, disk, terminal device, mode information processing device and conversion device have the greatest influence on the technical prospect of computers.

The new generation computer is an intelligent computer system integrating information collection, storage and processing, communication and artificial intelligence. It can not only deal with general information, but also face knowledge processing, and has the ability of formal reasoning, association, learning and explanation, which will help human beings to explore unknown fields and acquire new knowledge.

The development of computing technology in China In the history of human civilization, China once wrote a glorious page on the invention and creation of early computing tools. As early as Shang Dynasty, China created decimal notation, which was more than 1000 years earlier than the world. In the Zhou Dynasty, the most advanced computing tool at that time-calculation and compilation was invented. This is a small stick made of different colors of bamboo, wood or bone. When calculating each math problem, we usually make up a set of algorithms in the form of songs, and rearrange the sticks constantly while calculating. Zu Chongzhi, an ancient mathematician in China, calculated that pi was between 3. 14 15926 and 3. 14 15927. This result is earlier than that of the west 1000 years.

Abacus is another original creation of China, and it is also the first major invention in the development history of computing tools. This kind of light, flexible, portable and closely related to people's lives first appeared in the Han Dynasty and gradually matured in the Yuan Dynasty. Abacus calculation not only played a beneficial role in China's economic development, but also spread to Japan, Korea, Southeast Asia and other regions. It has stood the test of history and is still in use today.

China invented the South Guide Car, Water Elephant, Drum Car and Jacquard Machine, which not only made outstanding contributions to the development of automatic control machinery, but also had a direct or indirect impact on the evolution of calculation tools. For example, the water transport constellation map made by Zhang Heng can automatically synchronize with the earth's operation. After improvement in the Tang and Song Dynasties, it became the earliest astronomical clock in the world.

The drum in memory is the earliest automatic counting device in the world. The principle of jacquard machine has an indirect influence on the development of computer program control. In ancient China, Eight Diagrams consisted of Yang and Yin, which had a direct impact on the development of computing technology. Leibniz wrote a paper on gossip, and systematically put forward a binary arithmetic algorithm. He thinks that the earliest binary representation in the world is China's gossip.

After a long silence, after the founding of New China, China's computing technology entered a new period of development, and successively set up research institutions, set up computing technology and devices and computational mathematics majors in colleges and universities, and set out to build China's computer manufacturing industry.

1958 and 1959, China successively manufactured the first small and large electron tube computers. In the mid-1960s, China successfully developed a number of transistor computers, and compiled compiler and other system software in ALGOL and other languages. In the late 1960s, China began to study integrated circuit computers. In the 1970s, small integrated circuit computers were produced on a large scale in China. After 1980s, China began to pay attention to the development and application of microcomputer system. Large computers, especially supercomputers, have also made important progress; Establish computer service industry and gradually improve the structure of computer industry.

In the research of computer science and technology, China has made great achievements in finite element calculation method, machine proof of mathematical theorem, Chinese character information processing, computer system structure and software. In terms of computer application, China has made remarkable achievements in the fields of scientific calculation and engineering design. Computer application research and practice are becoming more and more active in business management and process control.

Computer science and technology

Computer science and technology is a technical subject with strong practicability and rapid development based on mathematics, electronics (especially microelectronics), magnetism, optics and precision machinery. However, it does not simply apply the knowledge of some disciplines, but forms a set of theories, methods and technologies related to information representation, transformation, storage, processing, control and utilization through high integration.

Computer science is a science that studies various phenomena and scales of computers and their surroundings, mainly including theoretical computer science, computer system structure, software and artificial intelligence. Computer technology generally refers to the technical methods and means applied in the computer field, including computer system technology, software technology, component technology, device technology and assembly technology. Computer science and technology includes five branches, namely theoretical computer science, computer system structure, computer organization and implementation, computer software and computer application.

Theoretical computer science is a subject that studies the basic theory of computers. In the development of mathematics for thousands of years, people have studied various calculations and created many algorithms. The mathematical theory, which takes the essence of calculation or the algorithm itself as the research object, was only developed in the 1930s.

At that time, the algorithm theory established by several mathematical logic scholars, that is, computability theory or recursive function theory, had an impact on the formation of modern computer design ideas in the 1940s. Since then, the research on the mathematical model properties of real computers and their programs, as well as the research on computational complexity, has been developing continuously.

Theoretical computer science includes automata theory, formal language theory, program theory, algorithm analysis and computational complexity theory. Automata is the mathematical model of a real automatic computer, or the model of a real computer program. The task of automata theory is to study the model of this abstract machine. Programming language is a formal language, and the theory of formal language is divided into O ~ 3 languages according to the strength of language expression ability, which correspond to four automata such as Turing machine. Program theory is the theoretical basis for studying program logic, program complexity, program correctness proof, program verification, program synthesis, formal linguistics and program design methods. Algorithm analysis studies the properties of various specific algorithms. Computational complexity theory studies the general properties of algorithm complexity.

Computer system structure programmers see computer properties, focusing on the conceptual structure and functional characteristics of the computer, the functional allocation of hardware, software and firmware subsystems and the determination of their interfaces. The computer properties that programmers who use high-level languages see are mainly the properties of software subsystems and firmware subsystems, including the programming language and user interface of operating system, database management system and network software. The computer properties that programmers who use machine language see are the conceptual structure of hardware subsystem (hardware subsystem structure) and its functional characteristics, including instruction system (machine language), register definition, interrupt mechanism, input and output mode, machine working state and so on.

The typical structure of hardware subsystem is Von Neumann structure, which is composed of arithmetic controller, memory and input and output devices, and adopts "instruction-driven" mode. At first, it was designed for solving nonlinear and differential equations, and did not foresee the emergence of high-level languages, operating systems and other special requirements to adapt to other application environments. For a long time, software subsystems have been developed on the basis of this von Neumann structure. However, the inadaptability is gradually exposed, which promotes the reform of computer architecture.

Computer organization and implementation is to study the functions of computers, the interconnection and interaction between components, and technologies related to computer implementation, all of which belong to the tasks of computer organization and implementation.

After the computer system structure determines the functions assigned to the hard subsystem and its conceptual structure, the task of computer organization is to study the internal structure and interrelationships of each component in order to realize various functions and characteristics of the machine instruction level. This interconnection includes the arrangement, interconnection and interaction of various functional components.

With the expansion of computer functions and the improvement of performance, there are more and more functional components in computers, and the interconnection structure between them is becoming more and more complicated. There are three interconnection modes in modern times, which are centered on the central processing unit, memory or communication subsystem and interconnected with other components. The organizational model centered on communication subsystem closely combines computer technology with communication technology, forming important computer research and application fields such as computer network and distributed computer system.

The technical range related to computing implementation is quite extensive, including computer components, device technology, digital circuit technology, assembly technology and related manufacturing technologies and processes.

The research fields of software mainly include programming, basic software and software engineering. Program design refers to the process of designing and compiling programs, which is the basic link of software research and development. The content of programming research includes related basic concepts, norms, tools, methods and methodologies. The development characteristics of this field are: the transition from sequential programming to concurrent programming and currency sharing programming; Transition from unstructured programming method to structured programming method; Transition from low-level language tools to high-level language tools; The transformation from concrete method to methodology.

Basic software refers to the software that plays a fundamental role in the computer system. The software subsystem of a computer can be divided into two layers: the layer close to the hardware subsystem is called system software, which is used frequently, but has nothing to do with specific application fields; The other layer is directly related to the specific application field, called application software; In addition, there are softwares that support the research and maintenance of other softwares, which are called supporting softwares.

Software engineering is a process of researching and maintaining software with engineering methods and related technologies. The whole process of software research and maintenance includes concept formation, requirement definition, design, implementation, debugging and delivery, as well as maintenance with three meanings of revision, adaptation and perfection. The research content of software engineering involves the objects, structures, methods, tools and management related to the above-mentioned whole process.

The tasks of the software research system are: adopting formal methods in software engineering, so that all kinds of work in the process of software research and maintenance can be completed automatically by computers as much as possible; To build an efficient computer with high integration of software, firmware and hardware to adapt to the development of software.

computer industry

The computer industry includes two major departments, namely computer manufacturing and computer services. The latter is also called information processing industry or information service industry. Computer industry is an energy-saving and resource-saving industry with high added value and intensive knowledge and technology, which has great influence on national economic development, national defense strength and social progress. Therefore, many countries have adopted policies to promote the prosperity of the computer industry.

The computer manufacturing industry includes the production of various computer systems, peripheral equipment and terminal equipment, as well as the manufacture of related devices, components, devices and materials. As an industrial product, computers require products with inheritance, high cost performance and comprehensive performance. The inheritance of computers is especially reflected in software compatibility, which enables users and manufacturers to use the software developed in the past in new products, so that the high-priced software wealth can continue to play its role and reduce the time and cost for users to re-develop software. Improving cost performance is the goal and motivation of computer product update.

Generally, computer products provided by computer manufacturing industry only include hardware subsystems and some software subsystems. Usually, there is a lack of application software in the software subsystem to adapt to various specific application environments. In order to make computers work in a specific environment, it is necessary to design application systems and develop application software. In addition, the operation and maintenance of computers need technicians with professional knowledge, which is often not possible for a group of users.

In view of these social needs, some computer manufacturers attach great importance to providing users with various technical services and sales services. Some computer service organizations independent of computer manufacturers also began to appear in the 1950s. By the end of 1960s, the computer service industry had become an independent industry in the world.

Development and application of computer

The combination of computer science and technology of various disciplines has improved research tools and methods and promoted the development of various disciplines. In the past, people mainly conducted scientific and technological research through experiments and theories. Now, calculation and simulation have become the third research method.

The combination of computer and related experimental observation instruments can record, sort out, process, analyze and draw charts on the spot of experimental data, which significantly improves the quality and efficiency of experimental work. Computer aided design (CAD) has become an important means of high quality and automation in engineering design. In theoretical research, computer is an extension of human brain, which can replace and strengthen some functions of human brain. In ancient times, mathematics was operated by paper and pencil. Now, computers have become new tools, and heavy mental work such as proving mathematical theorems may be completed or partially completed by computers.

As a new research method, calculation and simulation often lead to new branches of some disciplines. For example, with the appearance of high-speed computers and related calculation methods, the "computational obstacles" faced by aerodynamics, meteorology, elastic structural mechanics and application analysis began to break through, and some marginal branches such as computational aerodynamics and meteorological numerical prediction were derived. Computer quantitative research plays an important role not only in natural science, but also in social science and humanities. For example, computers are powerful tools for census, social investigation and natural language research.

The wide application of computers in all walks of life will often produce remarkable economic and social benefits, which will lead to major changes in industrial structure, product structure, management and service methods. In terms of industrial structure, emerging industries such as computer manufacturing, computer services and knowledge industries have emerged.

Microprocessors and microcomputers have been embedded in electromechanical equipment, electronic equipment, communication equipment, instruments and household appliances, making these products develop in the direction of intelligence. Computers are introduced into various production process systems, which greatly improve the automation level of chemical, petroleum, steel, electric power, machinery, paper, cement and other production processes, improve labor productivity, improve quality and reduce costs. The computer can be embedded in various weapons and systems, which can significantly improve its combat effectiveness.

In business management, computers can be used to complete statistics, planning, inquiry, inventory management, market analysis, decision-making and so on. To make enterprise management scientific and efficient, thus accelerating capital turnover, reducing inventory level, improving service quality, shortening new product development cycle and improving labor productivity. In office automation, computers can be used for document drafting, retrieval and management, which greatly improves office efficiency.

Computers are also people's learning tools and life tools. With the help of home computers, personal computers, computer networks, database systems and various terminal devices, people can learn various courses, obtain various information and knowledge, and handle various daily affairs (such as booking tickets, shopping, depositing and withdrawing money, etc.). ), even working from home. More and more people will come into direct or indirect contact with computers in their work, study and life. Popularizing computer education has become an important issue.

In a word, the development and application of computers is not only a technical phenomenon, but also a political, economic, military and social phenomenon. All countries in the world are trying to actively control the process of social computerization and informatization, overcome the possible negative factors in the process of computerization, and move forward to a higher level more smoothly.

The wheel of the times is about to enter the door of 2 1 century. How will people face the future? No matter what you do or where you live, you will realize that the century we are facing is an information age with highly developed technology. Computer is the main tool for information processing. Mastering computer knowledge has become an indispensable part of contemporary human culture, and computer skills are an indispensable basic means for people's work and life.

Based on this understanding, in recent years, China has set off a nationwide upsurge of learning computers, and people from all walks of life are eager to learn computer knowledge and master computer skills. For the majority of non-computer majors, the purpose of learning computer is to apply what they have learned, hoping to apply what they have learned and get immediate results, without learning system theory.

The key to mastering computer skills is practice, and only through a large number of practical applications can we truly master it deeply. It is difficult to really master computer applications just by reading books. Just as you can't swim at school on land, you must learn to swim in the water. Similarly, to learn computer applications, you must also sit next to the computer and operate the computer frequently and repeatedly. Practice makes perfect. As long as you do it right, the more time you spend on the computer, the greater the gain. ......