Classification on the basis of size and function
On the basis of size and function, computers are divided into mainframe, mini, micro and super computers. Personal computers, note books, netbooks, tablets, laptops, workstations, and palmtops are different forms of microcomputers.
1. Mainframe Computer :- In mainframe computer the main computer is kept at a central place. Which stores all the data and instructions. The user connects to the mainframe computer through the Dumb Terminal and uses the central database and processing capacity.
Mainframe computers are very large in size. Their data storage capacity is high and the speed of data processing is fast. By connecting to the mainframe computer, many people can do different tasks at the same time. Hence it is called multiuser computer. In this, a large amount of data processing can be done by staying online. Processing capacity is increased by connecting two or more microprocessors together in a mainframe computer. They usually use 32 or 64 bit microprocessors. Time Sharing Operating System and Multi Programming Operating System are used in mainframe computers.
Uses :- Mainframe computers are used in the fields of big companies, banks, railway reservation, defence, research, space science, etc.
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| Mainframe Computer |
2. Mini Computer :- They are smaller in size than mainframe computer while bigger than micro computer. It was invented in 1965 by a company called DEC (Digital Equipment Corporation).
In this, more than one micro processor is used. It has high storage capacity and speed. Many people can work on this at the same time. So there is shared use of resources.
Use :- In Passenger Reservation, Large Office, Company, Research etc.
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| Mini computer (PDP-8) |
3. Embedded Computer : - A small computer connected to any equipment such as television, washing machine, microwave, tax etc., which is prepared for a particular task, is called embedded computer. Embedded computer is in the form of a microprocessor or integrated chip which simplifies the working of that device.
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| Microwave (Example of Embedded Computer) |
