What is Analog Computer?

The word Analog means a continuously signal or a circuit or device designed to handle such signals. The opposite is “discrete” or “digital”.
 For example, the turning of a wheel or changes in voltage can be used as input. Analog computers are said to operate in real-time and are used for research in design where many different shapes and speeds and be tried out quickly. A computer model of a car suspension allows the designed to see the effects of changing size, stiffness, and damping.
What is Analog Computer

Analog Computer Photo:

Analog computer work by converting data into electrical signals. Here the electrons flow continuos in the form of a continuous signal exactly according to input. Abacus side rule, Milometer, Odometer, etc. are analog devices but not computers. Analog computers are seldom used by the public.
A typical analog device is a clock in which the handles move continuously around the face. Such a clock is capable of indicating every possible time of day. In contrast, a digital clock is capable of representing only a finite number of times (every tenth of a second, for example).
In general, humans experience the world analogically. Vision, for example, is an analog experience because we perceive infinitely smooth gradations of shapes and colors. Most analog events, however, can be simulated digitally. Photographs in the newspaper, for instance, consist of an array of dots that are either black or white. From afar, the viewer does not see dots (the digital form), but only lines and shading, which appear to be continuous. Although digital representation is approximations of analog events, they are useful because they are relatively easy to store and manipulate electronically. The tick is in converting from analog to digital, and back again.
             Analog computers serve as models for and simulate the relations of an actual physical system, usually operating in real-time, while digital computers compound primarily arithmetic data unrelated to the system represented.
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