$BTC Bitcoin (BTC) is the first decentralized cryptocurrency, created in 2009 by an individual or group under the pseudonym Satoshi Nakamoto. It functions as an electronic cash system that allows direct transactions between users without intermediaries, using a technology called blockchain to securely and transparently record all transactions. The supply of Bitcoin is limited to 21 million units, which contributes to its value. Although it is used as a medium of exchange, its high volatility has led to debates about its role as a store of value. In 2021, El Salvador adopted it as legal tender.