BADI

• Business Add-Ins  is the enhancement technique based on ABAP objects.
• Business Add-Ins can be used to customize the logic according to requirement or they can use the standard logic one available.

Two different view of BADI

1. Definition View
2. Implementation View  

• Definition View : - 

1. In the definition view, an application programmer predefined exit points in a source that allow specific industry sectors, partners and customers to attach additional functionality to  standard SAP source code without having to modify the original object.
2. To find out the BADI definition Transaction code : SE18.
3. BADI definition are Interface .

• Implementation View :- 

1. The users of Business Add-Ins can Enhance(customize) the logic they need or use a standard logic if one is available.
2. To implement BADI Transaction code : SE19.
3. BADI  implementation are Class.

Note :- Generally BADI are Defined by SAP in the standard Applications ( programs , Screens , Menus, ..) and Implemented by the customers.

• Program Enhancements: Functional enhancements of the program are defined in the form of interface methods and can be used with or without Menu Enhancements or Screen Enhancements 
• Menu Enhancements: Function codes can be entered for a BADI for the corresponding menu entries in the user interface definition.  
• Screen Enhancements: Sub screen areas can be entered for a Business Add-In. Screen enhancements can be implemented for these in the form of sub screen screens.