What is a computer ? and its history

A computer is generally defined as " an electronic device that takes information as input and  processing the information to produce output"                                                  or an electronic device which is capable of receiving information (data) in a particular form and of performing a sequence of operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.Is calculator computer?. Yes by above definition we can say calculator is computer. 

Fig 1. Computer

History of Computer:

Charles Babbage is father of the computer. A mathematician, philosopher, inventor and mechanical engineer, Babbage is best remembered for originating the concept of a programmable computer.

Fig 2.Charles Babbage

Charles Babbage was born in London Dec. 26, 1791, St. Stephan day, in London. He was son of Benjamin Babbage, a London banker.

In Babbage's times there was a really high error rate in the calculation of math tables, when Babbage planned to find a new method that could be use to make it mechanically, removing the human error factor. This idea started to tickle his brain very early, in 1812.

Then he invented difference engine, Analytical Engine

A difference engine is an automatic mechanical calculator designed to tabulate polynomial functions. The name derives from the method of divided differences, a way to interpolate or tabulate functions by using a small set of polynomial coefficients.

Fig 3.difference engine

The Analytical Engine was successor to Babbage's difference engine, a design for a mechanical computer. The Analytical Engine incorporated an arithmetic logic unit, control flow in the form of conditional branching and loops, and integrated memory, making it the first design for a general-purpose computer.

Fig 4.Analytical Engine