(DCL) Data Control Language : 

1-Data Control Language is used to define database access privileges for users.
2-Data Control Language mostly used in corporate sector.

Basically two main commands are used in DCL :

1-Grant :With the help of "Grant" command we give  database access privileges to the user.
2-Revoke:The "Revoke" command removes user access rights or privileges to the database objects.

Transaction Control Language(TCL) : 

1-Transaction Control Language play main role in Sql.
2-TCL  statements are used to manage changes made by DML Statements .
3-It allows statements to be grouped together into logical transaction.