Classification of Computers

DIGITAL, ANALOG AND HYBRID

Computers are of three basic types – Digital, Analog, and Hybrid. Current use of the word “computer” almost always refers to the electronic digital computer which uses solid-state electronic circuits.

1. Analog: This type of computer can process continuously varying quantities rather than on-off or incrementally stepped quantities, which are the inputs for the digital computer. The moving pointer type automobile speedometer is an example of a simple mechanical analog computer. Its input is the continuously variable rotational speed of the drive shaft and its output is the pointer movement across the dial which indicates the speed of the vehicle.
2. Digital: A digital computer uses the properties of electronic circuits which represent exactly two states – “on” or “off”. All digital computers use a combinatorial sequence of binary digits ‘0’ and ‘1’ to represent independent pieces of information. Digital computers are commonly used in business commercial applications.
3. Hybrid: An effort to combine the best features of Analog and Digital computer resulted in the design of Hybrid computers. This “dual purpose” system combines the measuring capabilities of the analog computer and the logical and control capabilities of the digital computers. Flight simulator is an example of Hybrid computer.