DATABASE - ACID is an acronym that stands for Atomicity, Consistency, Isolation, and Durability. It is a set of properties that guarantee that database transactions are processed reliably. Atomicity refers to the property of an ACID transaction that ensures that all parts of the transaction are processed as a single unit of work, and either all of the transaction succeeds or none of it does. Consistency refers to the property of an ACID transaction that ensures that the database remains in a valid state both before and after the transaction. Isolation refers to the property of an ACID transaction that ensures that transactions are executed independently of each other. Each transaction should not interfere with other transactions, even if they are being executed at the same time. Durability refers to the property of an ACID transaction that ensures that once a transaction has been committed, it will remain in the database even in the event of a system failure. An ACID-compliant database management system (DBMS) is one that supports transactions that adhere to these properties. ACID compliance is important for mission-critical applications where data integrity is paramount, such as financial systems, inventory management systems, and airline reservation systems.