What does ACID mean in databases?

Answer

ACID is a set of guarantees that make database transactions reliable: Atomicity (a transaction either fully completes or fully rolls back), Consistency (a transaction moves the database from one valid state to another), Isolation (concurrent transactions do not interfere with each other), and Durability (committed changes survive crashes). These properties are the foundation of relational databases and are essential for workloads like financial transfers. The opposing model, often called BASE, relaxes some of these guarantees for higher availability and scale.