What are ACID properties in the context of database transactions?

ACID is a set of properties that guarantee reliable transactions in databases:

• Atomicity: a transaction is completed in its entirety or not at all. If something goes wrong, all changes are rolled back.
• Consistency: after a transaction completes, the database remains in a correct state, satisfying all constraints and rules.
• Isolation: concurrent transactions do not affect each other as if they were executed sequentially.
• Durability: once a transaction is committed, the changes are saved and not lost even in case of failures.

These properties ensure the correctness and reliability of data operations in a multi-user environment.