ACID is Atomicity, Consistency, Isolation and Durability.
Atomicity : Operations that are bundled together and projected a single unit of job.
Consistency : Guarantees that after a transaction has taken place, there will be consistency.
Isolation : Helps protect viewing of other simultaneous incomplete transaction results.
Durability : Ensures durability by keeping a transitional log by which the permanent data be recreated by again applying the steps involved.
