Rollback is a process used in computing and data management to revert a system or database to a previous state. This is often necessary when an error occurs, such as a software bug or data corruption, allowing users to recover lost or damaged information. Rollback ensures that the system can return to a stable condition without losing important data. In databases, rollback is typically implemented through transactions, which are sequences of operations that can be committed or undone. If a transaction fails, the system can execute a rollback to restore the database to its last consistent state, ensuring data integrity and reliability in applications like SQL databases.