Transition to Web3 - Course 3 | How Smart Contracts Work
Users can trigger the existing code pieces (“smart contracts”) on a blockchain to execute them with the inputs they want.
Every smart contract is associated with an account. Users also have accounts. When a user wants to trigger (“call”) a smart contract, that user creates a transaction to the smart contract account.
For example, someone can trigger the buyBook program by calling its account as follows:
Alice -> buyBook($10)