DML: DML stands for Data Manipulation Language. DML is used to retrieve, store, modify, delete, insert and update data in database.
Examples of DML statements: SELECT, UPDATE, INSERT, DELETE statements.
DDL: DDL stands for Data Definition Language. DDL is used to create and modify the structure of database objects.
Examples: CREATE, ALTER, DROP statements.
DCL: DCL stands for Data Control Language. DCL is used to create roles, grant and revoke permissions, establish referential integrity etc.
Examples: GRANT, REVOKE statements
TCL: TCL stands for Transactional Control Language. TCL is used to manage transactions within a database.
Examples: COMMIT, ROLLBACK statements