Computer

Commonly Operated Machine Particularly Used in Trade, Education & Research
This article is about the machine.
The NASA Columbia Supercomputer.

A computer in a wristwatch
A computer is a programmable device, usually electronic in nature, that can store, retrieve, and process data. The first programmable electronic computers date to the mid-2oth century (around 1940-1941), although the concept and various non-electronic and analog models date back before this. Early electronic computers were the size of a large room, and their thermionic valve technology demanded huge amounts of power. Today, computers are based upon tiny integrated circuit, are hundreds of millions to hundreds of billions of times more powerful, and simpler computers can be made small enough to fit into a wrist watch and powered by a simple watch battery watch battery.
personal computers and their portable equivalent, the laptop computer, have come to be an integral part of the modern information age; they are what most people think of as "a computer". However, the most common form of computer in use today is by far the embedded computer. Embedded computers are small, simple devices that are often used to control other devices—for example, they may be found in machines ranging from fighter aircraft to industrial robots, digital cameras, consumer electronics,kitchen and other domestic appliances, hi fi components, cars and other vehicles, medical devices such ashearing aids, mobile phones and children's toys.
The ability to store and execute programs makes computers extremely versatile and distinguishes them from calculators. The church-turing thesis is a mathematical statement of this versatility: Any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with capability and complexity ranging from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks as long as time and storage capacity are not considerations