The book is divided into five sections, each focusing on a particular aspect of COM and ATL development. The book begins with a review of object-oriented and interface-based programming techniques, then moves into the core aspects of COM, including a full examination of language independence and location transparency. The author illustrates the numerous CASE tools used during ATL development and discusses apartments, COM exceptions, object identity, and component housing, in addition to various advanced concepts such as COM categories and tear-off interfaces. The fourth section examines a number of “COM patterns” such as enumerators, collections, scriptable objects, and callback interfaces. The book closes with an investigation of using ATL as a windowing framework and wraps up with the development of a full-blown animated ActiveX control using ATL.