What is difference between SET SCREEN and CALL SCREEN ? | ABAP Module Programing

- With SET SCREEN the current screen simply specifies the next screen in the chain , control branches to this next screen as sonn as th e current screen has been processed .Return from next screen to current screen is not automatic .It does not interrupt processing of the current screen.If we want to branch to the next screen without finishing the current one ,use LEAVE SCREEN.