Generation of computer systems which is available in different languages in English, Hindi and Tamil etc and in today generation their are seven generation available of computer but we will discuss only five and rest update later.
1. First generation of computer: The first generation of computer notes refers to those computers, which relied on upon and used vacuum tubes for storing and processing data. The computers were massive in size, could be located in a large room and had limited memory and processing capability. The Electronic Numerical Integrator and Calculator (ENIAC), for example, had only 20 storage registers and could accomplish 5000 additions per second. The vacuum tubes generated a lot of heat, consumed a great deal of power and had a very short span of life. Resultant, the Mean Time between Failures (MTBF) was low of the order of an hour. The computers were used by technical people mainly for scientific and engineering work. The maximum primary memory size was reported to be around 2KB (2024 bytes) and the speed of about ten thousand instructions per second. Computer programming was mainly carried out in Machine Language and later in Assembly Language.
2. Second generation of computer: The second-generation computer used transistors made of germanium semi-conductor material instead of the vacuum tubes, for storing and processing data.
Transistors were more compact in size and more reliable. Transistors consumed less power, and consequently, the MTBF became longer. It is said that the electronics were about ten times more reliable, ten times faster, consumed one-tenth of power, occupied about one-tenth of space and were ten times cheaper than the first-generation computers. The memory size and processing speed/capability also went up simultaneously. A typical second-generation computer could have up to 32 KB of RAM and speed up to 2,00,000 to 3,00,000 instructions per seconds. The years 1956-63 also witnessed the emergence of magnetic core memory and development of high- level language like ALGOL, COBOL, FORTRAN, and SNOBOL. Resultantly, computers became more widely accepted and used. Computers, which were earlier used for technical, scientific work, were now recognized by the industry and business. During this period, the business and applications of computers were mainly in the areas of payroll, inventory, production planning, marketing, and accounting.
3. Third generation of computer: The third-generation computers emerged with the introduction of a newer technology the integrated circuits/chips. The third generation of computers witnessed transistors being replaced by silicon chips more popularly known as the integrated circuits/chips. The ICs were circuits consisting of transistors, resistors, and capacitors grown on a single chip of silicon. ‘the integrated circuits/chips were made by printing hundreds, and later thousands, of tiny transistors on small silicon chips called semi-conductors. The integrated circuits/chips further revolutionized computer processing. Switching speed of transistors went up by a factor of 10, reliability increased by a factor of 10, power dissipation declined by a factor of 10 and size reduced by a factor of 10.
The cumulative effect was the emergence of extremely compact, yet powerful, computers. Computer memories expanded to 2 MB of RAM and processing speed of CPU went up to 5 Million Instructions per Second (MIPS). The improved/increased CPU capabilities led to the development of time-shared operating systems made online systems feasible and led to the emergence of Integrated Database Management Systems. There were further improvements in high-level languages. It was during this period/generation that it became possible for people without extensive technical training to make use of computers, making it possible for computers to enlarge their role in business, thanks to newly developed systems like dynamic production control systems, airlines reservation systems, interactive query systems, etc.
4. Fourth generation of computer: The computers, which we handle today, belong to the fourth generation, which extends from 1980 to the present. The fourth generation computers are characterized by the use of Very Large Scale Integrated Circuits (VLSICs) which are packed with as many as 2,00,000 to over 3 million circuits per chip. As a result, the power of a computer that once took up a large room now became as small as a desktop/tower top/laptop and even palmtop. The VLSIC technology has fuelled a growing movement towards microprocessors and micro-miniaturization the proliferation of computers that are so small, fast and cheap that they have become ubiquitous. Computer memory size has accelerated/gone up to over 2 gigabytes in large commercial machines, processing speeds having exceeded 200 MIPS.
The fourth-generation computers have been instrumental in Making possible/available extremely powerful Personal Computers (PCs) at relatively lower costs.
• Spreading computers from offices to homes.
• Decentralising computer organizations.
• Making networks and distributed data processing a reality.
• Developing interactive graphic devices and language interfaces for a visual system.
• Providing impetus to CAD/CAM.
• Ushering in the “Computer Culture.”
5. Fifth generation of computer: Fifth-generation computers are expected to use parallel processing and massively parallel processing. They will be using artificial intelligence and intricate mathematical models. They will be able to blend voice, images and extensive data from various sources.