computers

A computer is a machine that manipulates data according to a set of instructions.
Although mechanical examples of computers have existed through much of recorded human history, the first electronic computers were developed in 1940. These were the size of a large room, consuming as much power as several hundred modern personal computers.

Modern computers based on integrated circuits are millions to billions of times more capable than the early machines, and occupy a fraction of the space.

The ability to store and execute lists of instructions called programs makes computers extremely versatile, like the calculators. Any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore computers ranging from a mobile phone to a supercomputer are all able to perform the same computational tasks, given enough time and storage capacity.