What is difference between Multi tasking and Multi threading

Difference between Multi tasking and Multi threading :

• MultiThreading are the approach of which allows a single program to perform multiple activities simultaneously.
• Where as MultiTasking was a traditional approch which allows multiple programs to execute at a given point of time which is generally supported by the Operating System.    

                 DOS was a single Tasking Operating System.

                  Windows and Unix are MultiTasking O.S

• MultiThreading is generally supported by the language with the help of Operating System.