SAP Application is developed by ABAP - Advance Business Application Programming. ABAP/4 is the programming in 4th generation or we call 4GL in SAP release 3.0. In SAP release 4.0 or upper, it's called ABAP. In part of Run-Time or Kernel of SAP, it's developed from C/C++. In term of Implementation, SAP provide a function that is called "Customization" of "Configuration". It's a function that SAP all SAP Implementer to change parameter via Implementation Guide (IMG).
