A smart contract is a program that is stored directly on the blockchain and runs there automatically. It works according to fixed, programmed rules: when a certain condition occurs, it carries out the intended action without any human having to intervene.
Key properties
- Public: The code is stored on the blockchain and can be viewed by anyone. For verified contracts, this is even possible in plain text.
- Automatic: It does exactly what it was programmed to do. No more and no less.
- Hard to change: Once published, the code usually cannot be changed. Some contracts, however, are deliberately built so that the operator can adjust functions later. It is worth checking.
Limits
A smart contract is only as good as its code. Programming errors or deliberately built-in backdoors are executed just as reliably as everything else. So “smart contract” does not automatically mean “secure”.
Practical example
The Wallet Status on this site reads your values directly from a smart contract on the BNB Smart Chain, without going through a provider.