What are the different types of computers according to size performance and purpose?

Answer 1

There are four broad classification's, these are based on the very different electronic constructions used to interface the processor (CPU) to the components such as RAM (memory) and other devices used for storage, communications etc.

From biggest / most powerful to least:

...super computer - used in scientific research, weather forecasting etc

...mainframe - used by big businesses, banks etc for holding vast amounts of historical transaction data etc.

...minicomputer - used for technical work, running factories etc.

...microcomputer - used for just about everything else

Microcomputers are further subdivided by size/packaging, the distinction is not always clear:

...personal computer - a main box containing all the electronics with external monitor, keyboard etc. normally connected via wires.

...laptop or notebook computer - a single easily portable box with everything built-in and able to run on internal batteries.

...netbook - a small notebook with limited functionality when not connected to an external network (e.g. the internet)

...integrated or embedded - a microcomputer built into some other 'intelligent' device and not directly usable as a computer

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