ABAP: Programming (BC-ABA)
ABAP (Advanced Business Application Programming) is an SAP programming language and a component of the SAP NetWeaver application platform. Most commercial applications offered by SAP are written in ABAP. Application developers at SAP use ABAP to program SAP application components. SAP partners and customers use ABAP to program their own applications or to enhance the standard systems delivered by SAP and modify them to their own requirements.
The ABAP programming language is documented in full by the ABAP keyword documentation provided as part of an AS ABAP (Application Server ABAP). Among other things, it contains an integrated library of examples including executable example programs, a comprehensive ABAP glossary, and an overview of changes, release by release. When editing ABAP source code, this documentation can usually be displayed by choosing F1 or the blue information button. Other ways of displaying the ABAP keyword documentation are the transactions ABAPDOCU and ABAPHELP. An http service for displaying ABAP keyword documentation in the browser is also available.
The documentation here provides you with an introductory overview of ABAP.
ABAP: Fundamental Language Elements