$BTC First decentralized cryptocurrency, launched in January 2009 by the pseudonymous Satoshi Nakamoto. It enables peer‑to‑peer value transfers without intermediaries .

Operates on a proof-of-work (PoW) blockchain secured by SHA‑256 mining. Blocks are produced roughly every 10 minutes, with difficulty adjusting approximately every 2,016 blocks (≈2 weeks) to maintain this cadence .