Transaction
In plain terms
A group of operations treated as a single all-or-nothing unit.
Going deeper
A database transaction ensures multiple operations either all succeed or all roll back, preserving data integrity. It's bounded by begin/commit/rollback.
Under the hood
Provides ACID guarantees; isolation levels balance consistency against concurrency.
Examples
Bank transfers, order checkout, BEGIN/COMMIT, multi-step updates.
Think of it like...
Like a money transfer that either fully completes both sides or not at all.