A first for search and rescue from space

Between September 1982 and December 2020, at least 51,512 people were rescued on land and at sea with help from a network of Earth-orbiting satellites able to detect and locate emergency distress beacons.

Energy & Green Tech

How to make full use of wind energy in a compact city

Wind can be used as a renewable energy source that is clean, uncontaminated, and inexhaustible. Such characteristics have helped wind energy technologies to a key contributor to sustainable development in society, which is ...

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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 the mid-20th century (1940–1945). These were the size of a large room, consuming as much power as several hundred modern personal computers (PCs). 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. Simple computers are small enough to fit into a wristwatch, and can be powered by a watch battery. Personal computers in their various forms are icons of the Information Age and are what most people think of as "computers". The embedded computers found in many devices from MP3 players to fighter aircraft and from toys to industrial robots are however the most numerous.

The ability to store and execute lists of instructions called programs makes computers extremely versatile, distinguishing 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 ranging from a mobile phone to a supercomputer are all able to perform the same computational tasks, given enough time and storage capacity.

This text uses material from Wikipedia, licensed under CC BY-SA