Enhancements and Modifications

1	What is a user exit?
	User exits (Function module exits) are exits developed by SAP. The exit is implemented as a call to a function module. The code for the function module is written by the developer. You are not writing the code directly in the function module, but in the include that is implemented in the function module. The naming standard of function modules for function module exits is: EXIT_<program name><3 digit suffix> The call to a function module exit is implemented as: CALL CUSTOMER.-FUNCTION <3 digit suffix>
2.	How to find a exit?
	Display the program where you are searching for and exit and search for CALL CUSTOMER-EXIT If you know the Exit name, go to transaction CMOD. Choose menu Utilities->SAP Enhancements. Enter the exit name and press enter. You will now come to a screen that shows the function module exits for the exit.
3.	What are the types of exits?
	a. Menu exits add items to the pull down menus in standard SAP applications. You can use these menu items to call up your own screens or to trigger entire add-on applications b. Screen exits add fields to screens in R/3 applications. SAP creates screen exits by placing special subscreen areas on a standard R/3 screen and calling a customer subscreen from the standard screen’s flow logic. c. Function module exits add functions to R/3 applications. Function module exits play a role in both menu and screen exits.
4.	Where can we search a user exit?
	In SMOD
5.	How do we implement a user exit?
	Go to CMOD create a project here include the exit that u want to use and within this exit write the appropriate logic that we want.

BADIS

1.	What are BADIS?
	BADIs are Business Add-Ins. The are used to provide custom extension of a standard functionality. BADIs are the new form of user exit. They use ABAP OO. The support multiple implementation. BADIs are defined in SE18 and implemented in SE19. Code in application checks to see if and implementation is "active" and calls it if it has been implemented.

Difference User Exits Vs Badi

Badis	User Exits
1. Object Oriented paradigm	1. The more traditional types, are ones controlled and implemented via CMOD/SMOD transitions as includes to function modules
2. BADI's can be used any number of times	2. USER-EXITS can be used only one time