Bitcoin is a decentralized digital currency created in 2009 by an anonymous person or group of people using the pseudonym Satoshi Nakamoto. It operates on a peer-to-peer network, enabling users to send and receive payments without the need for intermediaries like banks. Bitcoin transactions are verified by network nodes through cryptography and recorded in a public ledger called the blockchain.

Key aspects of Bitcoin include:
1. Decentralization: Bitcoin is not controlled by any central authority or government.
2. Limited Supply: Only 21 million bitcoins can ever be mined, which adds to its scarcity.
3. Mining: New bitcoins are created through a process called mining, where powerful computers solve complex mathematical problems to validate transactions.
4. Blockchain: The underlying technology that ensures transparency and security in transactions.
Bitcoin has been seen as a store of value, similar to gold, and is used both as an investment and a method for transferring money globally. It has also been subject to price volatility and regulatory scrutiny.