The first part, the Programmer's Guide, describes the toolkit's various features and explains in detail how to use them. It contains over 100 pages of example programs. For the reader's convenience, each chapter of the Programmer's Guide contains an application writer's section and a widget writer's section. The second part, the X Toolkit Specification, contains the full text of the X Consortium's official X Toolkit Intrinsics standard. This section describes the X Toolkit's capabilities more succinctly and precisely, and is the definitive reference source for answering questions about how a proper toolkit implementation is supposed to operate. This second edition is fully updated and revised to take into account the new features incorporated into X11 releases 5 through 7 of the X Window System. Explanatory material tells what features were introduced with each individual release.