BAPI

• A BAPI is a well defined Interface to process the data of a Business Application System , implemented as a method of an Object in Business Object Repository.
• BAPIs ( Business Application Programming Interfaces ) are the standard SAP interfaces.
• They play an important role in the technical integration and in the exchange of business data between SAP components , and between SAP and non-SAP components.
• BAPI’s are defined as methods for the business object types. As a result , both the object-oriented structures in SAP Systems and the opportunity for object-oriented access are offered.
• These object-oriented interfaces allow other components to directly access the application layer of an SAP system without having to know the specific implementation details.
• BAPIs are RFC Function Modules.
• BAPI's are processed without returning any screen dialogs to the calling application.

   Advantages of using BAPI's

• Business Standard
• Easy to use and Understand
• Object-Oriented access.
• Compatible with Different Communication Technologies.
• Follows Industry Standards.
•  Stability and Downwards Compatibility

Characteristics of BAPIs

• Naming Conventions.

           <Business object >.< BAPI Name > 

• Ex:

           Material.CheckAvailability

Data Consistency

• Each BAPI that creates an instance an object or updates the data of an object is responsible for database consistency. 
• All database changes are carried out completely ( All ) or not at all (None ).

Note : The COMMIT WORK command must not be executed by the BAPI itself. It must be executed by the calling program.

No Dialog Orientation

• BAPIs do not return dialog screens from the R/3 server system to the calling program.

Authorization

• Authorization is given for secure transaction.