Launched in 2009, Bitcoin is the world's largest cryptocurrency by market cap. Unlike fiat currency, Bitcoin is created, distributed, traded, and stored with the use of a decentralized ledger system known as a blockchain. Bitcoin's history as a store of value has been turbulent; the cryptocurrency skyrocketed up to roughly $20,000 per coin in 2017, but as of two years later, is currency trading for less than half of that. As the earliest cryptocurrency to meet widespread popularity and success, Bitcoin has inspired a host of other projects in the blockchain space.