What's the difference between SAP ABAP and SAP Basis?

"Basis" and "ABAP" are two technical terms specific to the SAP world that many often get confused.

ABAP, which stands for Advanced Business Application Programming, is one of the primary programming languages in which many of SAP's applications are written (the other language is Java). It began life as a pure procedural language and over the years has added object-oriented features that will be familiar to any Java programmer. ABAP programs are run on SAP's Netweaver ABAP application server, which is the only publicly available ABAP runtime environment. In most organizations, ABAP experts are developers and programmers."

Basis is the SAP version of system administration. In most non-SAP organizations, "Basis" people will be called "system administrators." Basis administrators are responsible for ensuring that the SAP application server and applications are installed and configured properly and remain running smoothly. Depending on the organization, SAP Basis administrators may also be responsible for configuring and maintaining the operating system and database that SAP is running on, but in many organizations there are other system administrators responsible for operating systems and databases that work with Basis experts to configure the full system.

The lines may start to blur in some circumstances. Many Basis administrators know a little ABAP, and many ABAP developers know a little Basis, but usually these competency areas remain fairly separate within organizations.