Bitcoin is a cryptocurrency first introduced on October 31 2008 with a computer science paper that described how it would work. A few months later, on January 3, 2009, the code was released and the first
bitcoins appeared.
Bitcoin is often compared to gold in that there is a limited supply — the maximum number of
bitcoins that will ever enter circulation is 21 million. Unlike gold, however, bitcoin is digital, making it far easier to divide, transfer, and store.