Features: large volume, high power consumption and poor reliability. It is slow (usually thousands to tens of thousands of times per second) and expensive, but it lays the foundation for the future development of computers.
The second generation: the operating system, high-level language and its compiler on the hardware side of transistor digital computer (1958— 1964). The application fields are mainly scientific calculation and transaction processing, and begin to enter the field of industrial control. It is characterized by smaller size, lower energy consumption, higher reliability, faster operation speed and better performance than 1 generation computers.
The third generation: integrated circuit digital computer (1964— 1970). In terms of hardware, small and medium-sized integrated circuits (MSI, SSI) are used as logic elements, and the magnetic core is still used as main memory. In terms of software, there are time-sharing operating systems and structured and large-scale programming methods. It is characterized by faster speed.
Features: the reliability is significantly improved, the price is further reduced, and the products are universal, serialized and standardized. The application field began to enter the field of word processing and graphic image processing.
The fourth generation: large-scale integrated circuits (1970 till now). In hardware, LSI and VLSI are used as logic elements. In software, database management system, network management system and object-oriented language have appeared. Its characteristic is that 197 1 year, the world's first microprocessor was born in Silicon Valley, USA, which initiated a new era of microcomputers.
Features: The application field is gradually moving from scientific calculation, transaction management and process control to family.
Development trend: Since the appearance of computers, the operation speed has been greatly improved, and the operation speed of the fourth generation computers has reached several billion times per second. Computers have also developed from being used only for military scientific research to being owned by everyone. The powerful application function of computer has created a huge market demand. In the future, computer performance should develop in the direction of miniaturization, networking, intelligence and giant.
Extended data:
Application field:
1, information management, information management is a computer technology based on database management system, which helps managers improve their decision-making level and business strategy. Information processing includes a series of work such as data collection, storage, processing, classification, collation, retrieval and release.
2, process control, process control is to use the computer to collect data in real time, analyze the data, and quickly adjust or control the controlled object according to the optimal value. Using computer to control the process can not only greatly improve the automation level of control, but also improve the timeliness and accuracy of control, thus improving working conditions and increasing output and qualified rate. Therefore, computer process control has been widely used in machinery, metallurgy, petroleum, chemical industry, electric power and other departments.
3. Auxiliary technology, computer-aided design is a technology that uses computer systems to assist designers in engineering or product design in order to achieve the best design effect. CAD technology has been applied to aircraft design, ship design, architectural design, mechanical design, large-scale integrated circuit design and so on. Using computer-aided design can shorten the design time, improve work efficiency, save manpower, material resources and financial resources, and more importantly, improve the design quality.
4. Multimedia applications. With the development of electronic technology, especially communication and computer technology, people have been able to combine various media such as text, audio, video, animation, graphics and images to form a brand-new concept-"multimedia". In the fields of medical treatment, education, commerce, banking, insurance, administration, military affairs, industry, broadcasting, communication and publishing, the application of multimedia has developed rapidly.
Main categories:
1, supercomputer, supercomputer usually refers to a computer composed of hundreds of thousands or even more processors, which can calculate large and complex problems that ordinary PCs and servers can't complete. Supercomputer is a computer with the strongest function, the fastest operation speed and the largest storage capacity, and it is an important symbol of the national scientific and technological development level and comprehensive national strength.
2. Network computers refer to some high-performance computers that can provide services to the outside world through the network. Compared with ordinary computers, it requires higher stability, security and performance, so it is different from ordinary computers in CPU, chipset, memory, disk system, network and other hardware. The server is the node of the network, which stores and processes 80% of the data and information on the network and plays an important role in the network.
3. Industrial control is a computer system that uses bus structure to detect and control the production process, its electromechanical equipment and process equipment. Industrial computer for short. It consists of computer and process input and output (I/O). A computer consists of a host, input and output devices, external disk drives and tape drives.
References:
Computer-Baidu Encyclopedia