Bitcoin: A Peer-to-Peer Electronic Cash System One-Liner Bitcoin is an anonymous digital coin that changes hands based on unique cryptographic keys, validated through a decentralized distributed (P2P) ledger that A) is publicly-run by transaction chronology verification from decentralized volunteer compute nodes that solve a “proof-of-work” (proof of this node’s goodwill) in exchange for the coin itself and B) incentivizes actors with malicious intent to support the system because it is more profitable for them to perform A rather than attack it (antifragile).