Can you name different levels of transaction isolation in database management systems?

Main transaction isolation levels in DBMS:

1. Read Uncommitted — a transaction can see changes made by other transactions even if they are not yet committed (possible dirty reads).
2. Read Committed — a transaction only sees data that has been committed by other transactions (prevents dirty reads).
3. Repeatable Read — guarantees that data read at the beginning of a transaction will not change until it ends (prevents non-repeatable reads).
4. Serializable — the strictest level, transactions are executed as if they were executed sequentially, one after another (prevents phantom reads).

Choosing an isolation level affects performance and data integrity.