Transactions Protocol
Actions define atomic behaviors within a smart contract. At a higher level, transactions define groups of actions that execute atomically within a decentralized application. Analogously to a database transaction, the group of actions that form a blockchain transaction must all succeed, one by one, in a predefined order, or else the transaction will fail. To maintain transaction atomicity and integrity in case of a failed transaction, the blockchain state is restored to a state consistent with the state prior to processing the transaction. This guarantees that no side effects arise from any actions executed prior to the point of failure.