Smart Contracts
A smart contract is a program stored on a blockchain that runs automatically when its conditions are met.
In depth
Think of a vending machine: insert the right coins, press a button, and the snack drops — no cashier needed. Smart contracts do the same for money and data, and because they run on the blockchain nobody can alter or stop them once deployed. Tokens, exchanges, lending markets and NFTs are all smart contracts.
Why it matters
Smart contracts are what turned blockchains from ledgers into platforms.