Different types of computers based on …

Computers are classified in to three types based on their principles of operation. These three types of computers are

Analog computers
Digital computers
Hybrid computers
Analog computers

Analog computer is a computer that performs operations using continuously varying signals such as voltage, current and frequency. In analog computers numbers are represented by continuously varying quantities such as voltage, current and frequency. 

Analog computers are mainly used for scientific and engineering purposes. These computers do not give completely accurate results. The accuracy of analog computers is less. Analog computers do not require memory for performing operations.

Antikythera mechanism is the first known analog computer that is designed to predict astronomical positions and eclipses. This instrument was designed and constructed by Greek scientists between 150 and 100BC.

Digital computers

Digital computer is a computer that performs calculations and logical operations using electrical signal such as voltage that is represented in two digits 0 and 1. Where 0 and 1 represents two different voltages or states, 0 represents 0V or OFF state and 1 represents 5V or ON state. 0 or 1 is called bit.

Most of the computers available today are the digital computers. The computers that we use at home or offices are digital computers.

Hybrid computers

Hybrid computer is a computer that has features of both analog and digital computers. These computers use analog part for performing the mathematical calculations such as differential equations and digital part for performing the logical operations and for storing result. Hybrid computers have the speed of analog computer and accuracy of digital computer.