Bitcoin is a form of digital currency, created and held electronically. Bitcoins aren’t printed, like dollars or euros – they exist in a virtual database called the Blockchain. This database is maintained by people, and increasingly businesses, running powerful computers all around the world, that uses software to process highly complex mathematical problems. In return for processing these math problems, people earn bitcoins.
Bitcoin is an example of a growing category of money known as cryptocurrency. Bitcoin can be used to buy things electronically. The thing that makes it different from conventional money is that no single institution controls the bitcoin network. Watch a video about bitcoin.