This chapter describes some simple ways of using GNAT to build executable Ada programs. Running GNAT, through Using the gnatmake Utility, show how to use the command line environment. Introduction to Glide and GVD, provides a brief introduction to the visually-oriented IDE for GNAT. Supplementing Glide on some platforms is GPS, the GNAT Programming System, which offers a richer graphical “look and feel”, enhanced configurability, support for development in other programming language, comprehensive browsing features, and many other capabilities. For information on GPS please refer to Using the GNAT Programming System.