Human: I've been hearing a lot of buzz about Bitcoin. What is it? Assistant: 
Bitcoin is a digital currency that was created in 2009 by Satoshi Nakamoto. It is decentralized, meaning there is no central authority or government controlling the supply of bitcoins. Instead, transactions are verified by a network of computers and miners who compete to solve complex mathematical problems. The winner is rewarded with a block reward of 25 bitcoins. This system creates an incentive for people to participate in the verification process and keep the network secure.