What is Bitcoin?
Bitcoin (BTC) is the original cryptocurrency. Introduced in a 2008 white paper by the pseudonymous Satoshi Nakamoto and launched in January 2009, it was the first system to solve the double-spending problem for digital money without relying on a central authority. Transactions are recorded on a public, append-only ledger - the blockchain - maintained by a global network of nodes that follow a consensus rule called Proof-of-Work.
Today Bitcoin is the largest cryptocurrency by market capitalization and is widely considered the benchmark digital asset. It is traded on every major exchange, held by public companies on their balance sheets, and serves as the settlement asset behind much of the broader crypto market.
How does Bitcoin work?
Bitcoin transactions are broadcast to a peer-to-peer network and bundled into blocks roughly every ten minutes. Miners compete to solve a cryptographic puzzle - a process that burns energy and secures the ledger - and the winner proposes the next block, collecting the block reward plus transaction fees.
The protocol issues new BTC on a schedule that halves roughly every four years. This disinflationary curve caps the total supply at 21 million coins and is enforced by every node on the network. Because anyone can run a node and verify the rules themselves, no single party can print more Bitcoin, censor transactions, or reverse the ledger unilaterally.