Computers are classified into 3 categories; Digital, Analog and Hybrid.
Digital: It is a counting device. The data are coded into Binary digits i.e. 0s and 1s. It manipulates the data that are given to it. These are further classified on the basis of use and size.
Analog: It works by measuring voltage by the supply of continuous electrical signals. Its output results continuously. eg.: Speedometer of a car, petrol pump meter etc. These have parallel functions as such it is very fast but the accuracy is only 99%.
Hybrid: It is a combination of digital and Analog Computers. Some calculations are done in Analog and the data then converts the signals into digital or vice versa. It uses a modem (Modulator Demodulator).
The types of computers that are based on size generally are Super Computers, Mainframes, Super Mini, Mini and Micro Computers. All these does one and the same thing ie. computation but the industry has given these names for identification purposes only.
Next: How Computers Remember?