Raspberry Pi is a series of small single board computers having roughly the size of a credit card. It is promoted and developed by the Raspberry Pi foundation, a charity based in the United Kingdom. The mission of the Raspberry Pi foundation is "to put the power of computing and digital making into the hands of people all over the world." This means to promote teaching of basic computer science in schools and in developing countries. To support this goal, the Raspberry Pi needs to be as cheap as possible to be affordable for many people. The Raspberry Pi does not even come with a case, and neither does have peripherals like mouse or keyboard. But with having standard connectors like HDMI for TVs or monitors and USB interfaces it is very easy to connect it as needed. Several generations of Raspberry Pis have been released and a lot of peripherals and devices are available now.

Raspberry Pi 4 (Photo by Jessie Green)

The Raspberry Pi was much more successful than originally anticipated, because it was discovered for use cases outside of its original purpose.

Find more information on the official Raspberry Pi website.