Explain the concept of transaction atomicity.

Transaction atomicity is a principle in database management that ensures a transaction is treated as a single, indivisible unit of work. This concept means that:

1. **All-or-Nothing:** Either all operations within the transaction are successfully completed, or none are applied. If any part of the transaction fails, the entire transaction is rolled back to its initial state.

2. **Consistency:** Ensures that the database remains in a consistent state before and after the transaction, regardless of whether it completes successfully or is rolled back.

3. **Isolation:** Guarantees that transactions are executed in isolation from one another, so the outcome of one transaction does not affect others until it is completed.

4. **Durability:** Once a transaction is committed, its changes are permanent and will survive system failures.

Atomicity is crucial for maintaining data integrity and reliability in systems that handle multiple concurrent transactions.