Bitcoin is the most popular cryptocurrency, both in terms of mainstream awareness as well as buy and sell volume. It is based on an open-source technology and operates with no central authority. This means that nobody owns or controls the network and everyone can take part. Bitcoin was conceived in 2008 by a person or group going by the name Satoshi Nakamoto, whose real identity is still unknown. Bitcoin’s supply is limited to a fixed number of 21,000,000 units.