The act of defining atomic behavior in smart contracts. At a higher level, transactions determine the group of actions that are carried out atomically in a decentralized application. By analogy with database transactions, the group of actions that make up a blocked transaction must all be successful, one at a time, in the order specified, or the transaction will fail. To maintain the atomity and integrity of the transaction if a transaction fails, the blockchain status is returned to a status that is consistent with the state before processing the transaction. This guarantees that no side effects arise from actions taken before the point of failure.