This definitive guide to ABAP/4 aims to make the fundamentals of this evolving programming language accessible to anybody developing or maintaining an SAP R/3 system. Starting with the basic principles, it explains the essential characteristics of ABAP/4 and the SAP programming concept. The accompanying CD-ROM contains sample programs used in this book for Version 3.0C but because many people are still running off older systems, a modified set of programs for systems running on Version 2.2E has also been included.