REXX combines the simplicity of a programming language such as BASIC with features that exist in more powerful languages such as C, PASCAL, or PL/1. Part of the success of REXX has been due in part to having been selected as the Systems Application Architecture Programming Language (SAA/PL). The purpose is to provide a common look and feel across all operating systems. This is important because CUA is the standard that the Workplace Shell uses which is also part of SAA. REXX provides the facility for the Workplace Shell to create, modify, and delete objects. This chapter describes the REXX functions and how to use them in Workplace Shell applications.