Bitcoin is a digital currency that enables users to make secure and anonymous payments online. It is decentralized, meaning it is not controlled by any government or central bank. Bitcoin transactions are verified and recorded on a public ledger, known as the blockchain, which is maintained by a network of computers.
Bitcoin is the first decentralized cryptocurrency. Based on a free-market ideology, bitcoin was invented in 2008 when an unknown person published a white paper under the pseudonym of Satoshi Nakamoto. Use of bitcoin as a currency began in 2009, with the release of its open-source implementation. From 2021 to 2025, El Salvador adopted it as legal tender currency before revoking it. As bitcoin is pseudonymous, its use by criminals has attracted the attention of regulators, leading to its ban by several countries.