# ACID
It is a set of properties for database transactions.
# Atomicity
Atomicity requires that each transaction be "all or nothing": if one part of the transaction fails, then the entire transaction fails, and the database state is left unchanged.
# Consistency
The consistency property ensures that any transaction will bring the database from one valid state to another.
# Isolation
The isolation property ensures that the concurrent execution of transactions results in a system state that would be obtained if transactions were executed serially, i.e., one after the other.
# Durability
The durability property ensures that once a transaction has been committed, it will remain so, even in the event of power loss, crashes, or errors.