A Business Application Programming Interface (BAPI) is a precisely defined interface providing access to processes and data in business application systems such as R/3. BAPIs are defined as API methods of SAP Objects. These objects and their BAPIs are described and stored in the Business Object Repository (BOR).
BAPIs can be called within the R/3 System from external application systems and other programs. A BAPI call can either be made as an object oriented method call or as a remote function call (RFC). BAPIs are a global communication standard for business applications.
Examples of what BAPIs can be used for include:
R/3 satellite systems
Distributed R/3 scenarios using Application Link Enabling (ALE)
Connecting R/3 Systems to the Internet using Internet application components (IACs)
Visual Basic programs as front ends to R/3 Systems
Work flow applications that extend beyond system boundaries