A smart contract is a program, stored on a blockchain, that holds and moves funds according to rules nobody can change after deployment.
What that buys
- No counterparty. The rules execute themselves; there is no company in the middle to agree to do what it said.
- No waiting. The action happens when the conditions are met, not when someone processes a request.
- Transparency. Anyone can read the code. What it will do is not a matter of trust.
What it costs
Code does not negotiate. There is no customer service, no discretion and no appeal. A bug that would be a support ticket is instead permanent, and the money moves anyway. Who audits this is the question that follows directly from that.
What a person should take from it
Smart contracts are the reason automated, transparent arrangements work at all. They are also the reason being careful matters more, not less: the same property that removes the counterparty removes the recourse. That is the trade described throughout choosing where to hold and keeping it safe.
Reading next
How the chain underneath works, then how an audit does and does not help.