Let's begin our discussion of Microsoft's technologies for writing distributed applications by looking at the Component Object Model (COM). COM is the foundation of all of the other technologies we will examine in this book. This chapter does not try to cover every detail of COM—many excellent books are available that already do this. Instead, you'll find just those topics you need to understand to successfully write applications using Microsoft Transaction Server (MTS). If you are interested in learning more about COM, several useful resources are listed in the bibliography.