What is a Computer?

A computer is an electronic device which senses or accepts input data, performs operations or computations on the data in a pre-arranged sequence of program, and provides the result as an output or action.

The basic difference between the computer and the calculator is that the computer can perform long sequences of computations without human interventions. It has the ability of storing and executing a given set of instructions for solving a particular problem.

The basic characteristics favoring the usage of computers are:

1. Volume: Whenever the volume of data is large and is subject to repetitive operations, computers can store and process the data to provide the desired information.
2. Speed: In situations where response requirement is quick, the only alternative is to use computers. For example, in Airline reservation systems, the response to a request from anywhere in the country has to be within a few seconds and hence computer-based systems have been introduced.
3. Accuracy: For scientific calculations, a high degree of accuracy is required and that too at a very high speed. Computers provide the capability for accurate and fast processing.
4. Complexity: When the applications involve complex algorithms, it will be difficult to solve them manually. For example, complex differential equations or Operations Research Algorithms like Linear Programing will necessarily require usage of computers.