History of the development of computers
The development of electronic computers has gone through five generations:
The first generation of electronic computers (1946-1958) used electron tubes as the logic components, which was known as the electron tube era;
The second generation of electronic computers (1959-1964) used transistors as the logic components of computers, which was known as the transistor era;
The third generation of electronic computers (1965-1970) with integrated circuits as logic components, known as the era of small-scale integrated circuits;
The fourth generation of electronic computers (1971-1989) large-scale integrated circuits are used in computers, registers, fast, known as the era of large-scale and ultra-large-scale integrated circuit;
The fifth generation is the era of developing computer science, mainly intelligent computers, distributed computer systems and multimedia technology.
I. History of computer development:
Based on the different physical devices used in computers, can be divided into four stages.
The first generation: electron tube computer, began in 1946, the structure of the CPU as the center, the use of machine language, slow, small storage capacity, mainly used for numerical calculations.
The second generation: transistor computer, began in 1958, the structure of the memory-centered, using high-level language applications expanded to data processing and industrial control.
The third generation: small and medium-sized integrated circuit computers, began in 1964, the structure is still memory-centered, adding a variety of external devices, software has been developed to a certain extent, the computer to deal with images, text and information to strengthen the function.
The fourth generation: large, very large-scale integrated circuit computers, began in 1971, more widely used, the emergence of microcomputers.
Computer hardware development at the same time, the software has always accompanied the pace of its rapid development, in terms of the computer’s programming language, also divided into three generations.
The first generation: machine language. Each instruction is encoded in binary, which is very inefficient.
The second generation: assembly language. Programmed in symbols, related to specific machine instructions, and inefficient.
Third generation: high-level languages: such as FORTRAN, COBOL, BASIC, PASCAL, etc. are high-level languages.
Two, the development of China’s computer
China began in 1956, electronic computer research and teaching.
In December 1983, the successful development of 100 million times per second of the “Galaxy” megacomputer;
November 1992, the successful development of 1 billion times per second of the “Galaxy Ⅱ” megacomputer;
1997 successful development of 13 billion times per second of the “Galaxy Ⅲ” megacomputer.
Three, the development trend of the computer
The development of the computer to the miniaturization and giant, multimedia and network development.
Basic Concepts of Computers
All information within a computer is represented in binary form in bits.
Bit: A computer recognizes only binary numbers consisting of 0s or 1s, and each 0 or 1 in a binary number is the smallest unit of information, called a “bit”.
Byte: is a unit of measurement of computer storage capacity. An 8-bit binary data unit is called a byte. Inside the computer, a byte can represent a data, can also represent a letter of the alphabet or other special characters, two bytes can represent a Chinese character.
Word: in the computer, as a whole unit for storage and processing of a group of binary numbers. A computer, the word binary number of bits is fixed.
Word length: a word contains the number of binary digits of the number of bits is called the word length. Word length is a technical indicator of the precision of a computer.
Storage Addressing: In order to facilitate the effective management and storage of data in the computer, the need for memory cells numbered, that is, give each storage unit an address. Each memory unit stores one byte of data. If you need to store a storage unit, you must first know the address of the unit, and then you can access the information on the unit.
Note: The address of a storage unit is different from the contents of the storage unit.
Instruction: a command that directs a computer to perform a basic operation.
Instruction system: a collection of all the instructions that a computer can execute.
Program: a sequence of instructions organized in certain processing steps that can accomplish certain processing capabilities.
Briefly describe the development of computers
The history of computer development can be divided into 1854-1890, 1890 – early 20th century, mid-20th century, late 20th century to the present, four stages.
Generation 1: Electron Tube Digital Machine (1946-1958)
Hardware, the logic element used is a vacuum electron tube, the main memory uses mercury delay line, cathode ray oscilloscope electrostatic memory, magnetic drums, magnetic cores; the external memory is used in magnetic tape. The software used is machine language, assembly language. Areas of application are dominated by military and scientific computing.
Disadvantages are large size, high power consumption, poor reliability. Slow speed (generally thousands to tens of thousands of times per second), expensive, but laid the foundation for future computer development.
Generation 2: transistor digital machine (1958-1964)
Software operating system, high-level language and its compiled program application areas to scientific computing and transaction processing, and began to enter the field of industrial control. Characterized by reduced size, reduced energy consumption, improved reliability, increased computing speed (generally 100,000 times per second, can be as high as 3 million times), performance than the first generation of computers have greatly improved.
Generation 3: Integrated Circuit Digital Machine (1964-1970)
Hardware, the logic element using medium and small-scale integrated circuits (MSI, SSI), the main memory is still using magnetic cores. On the software side, time-sharing operating systems as well as structured and scaled programming methods appeared. Characterized by faster, but also a significant improvement in reliability, the price fell further, the product towards generalization, serialization and standardization. Application areas are beginning to enter the field of word processing and graphic image processing.
Generation 4: large-scale integrated circuit computers (1970 to the present)
Hardware, logic components using large-scale and very large-scale integrated circuits (LSI and VLSI). In terms of software, database management systems, network management systems and object-oriented languages appeared, etc. In 1971, the world’s first microprocessor was born in Silicon Valley, the United States, creating a new era of microcomputers. Application areas from scientific computing, transaction management, process control gradually to the family.
Briefly describe the development of computers
The development of computers is as follows:
1. The first generation of computers
The main feature of the first generation of computers is the use of electron tubes as logic components, so usually people also call the first generation of computers as electron tube computers. Mercury delay line or cathode ray tube is used as the main memory, a magnetic drum is used as auxiliary storage, paper tape, card, tape, etc. are used for input and output, and programs are written in machine language and assembly language.
2, the second generation of computers
The hardware part of the second generation of computers used transistors as logic elements, the size of the reduced, but enhanced functionality, this generation of computers are also known as transistorized computers, auxiliary storage using ferrite cores and drums, disks, began to write programs in a high-level language, and appeared in the management program.
3, the third generation of computers
The hardware part of the third generation of computers used medium and small-scale integrated circuits instead of discrete components transistors, and therefore also known as medium and small-scale integrated circuit computers. The use of microprogramming and pipelining technology has increased the flexibility and speed of operation of the computer, and on the software side the management program has evolved into an operating system, and diagnostic programs have appeared.
The main features of the computer
1, high accuracy of calculation
The development of science and technology, especially the development of cutting-edge science and technology, requires a high degree of accuracy of calculation. Computer-controlled missiles can accurately hit the intended target, is inseparable from the computer’s precise calculations, the general computer can have a dozen or even dozens of effective digits, the calculation accuracy can be a few thousandths of a few millionths of a few, is beyond the reach of any computational tools.
2, logical computing power
Computers can not only carry out accurate calculations, but also has a logical function, can compare and judge the information. The computer can participate in the operation of the data, programs, and intermediate and final results saved, and can be judged according to the results of the automatic implementation of the next command for the user to call at any time.
What is the history of the development of computers?
1, the first stage of development: 1946-1956 the era of electron tube computers. 1946 the first electronic computer came out of the United States University of Pennsylvania, it was designed by von Neumann. Covering an area of 170 square meters, 150KW. computing speed is slow yet no one fast. It is a milestone in the history of computer development. (ENIAC) (electronicnumericalintegratorandcalculator) full name is “electronic numerical integrator and computer”.
Features: large size, power consumption, slow speed
2, the second stage of development: 1956-1964 transistor computer era: operating system.
Features: use of transistors as logic switching elements; use of magnetic cores as the main memory (memory), auxiliary storage (external memory) using disks and tapes; increase in the amount of storage, reliability; output and input methods have improved greatly; the beginning of the use of operating systems, with a variety of high-level languages.
3, the third stage of development: 1964-1970 integrated circuits and large-scale integrated circuits of the computer era (1964-1965) (1965-1970).
Features: computers became smaller, lower power consumption, faster, using an operating system that allows computers to run many different programs at the same time under the control and coordination of the central program
4, the fourth stage of development: 1970-present: the era of computers with ultra-large-scale integrated circuits.
Features: small size, fast computing speed, high system stability, low heat generation, easy maintenance.