Depending upon the way a system performs, a computer can be classified into the following types:
It works with digits and numbers. For example, to calculate the distance travelled by a car, you might take into consideration the diameter of the tyre to calculate the circumference, the number of revolutions of the wheel per minute, the time taken in minutes, and then multiply them all to get the distance moved. This is known as digital calculation.
Digital computers can be classified on the basis of size and capabilities into :-
This computer works on the principle of using continuous measurements of physical phenomenon like breath, rotation, electric effects, etc. Take the example of the principle of the milometer in a car. when the wheels of a car rotate, they make some gears to move. This movement is transmitted to the centre by a flexible shaft. The meter itself contains some gears/wheels marked with numerical numbers and is calibrated to calculate the exact distance travelled in metres or kilometres. In an analog computer, the input and output are continuously varying quantities such as voltage, instead of the discrete digits of digital computers.
There are some computes which employ both digital as well as analog quantities. these are known as hybrid computers. For example, a digital thermometer employs a mechanism which converts the temperature observed into digital form using analog-to-digital conversion. Hybrid computers are the computers that are generally used in the process of control environment, where an analog (or continuously varying) input is provided to a computer which processes it digitally and presents the output in the analog or digital form as required.