Definition
Proof of Work is a consensus mechanism used in some blockchains where participants must spend computing power to solve a mathematical puzzle before they can propose a new block of transactions. This process makes it costly to influence the ledger, helping the network agree on a single shared history and making it harder to alter past records.
In Simple Terms
Proof of Work is a method blockchains use to decide who gets to add the next block of transactions. Computers compete by doing intensive calculations, and the first to find a valid answer earns the right to add the block. Because this requires real computing effort, it helps protect the network from easy tampering.
Context and Usage
Proof of Work is commonly discussed when describing how certain cryptocurrencies secure their networks and choose which version of the ledger is valid. It appears in conversations about mining, energy use, network security, and how blocks are created and linked together. The term is central in explanations of how decentralized systems reach agreement without a central authority.