COM

COM is a platform-independent, distributed, object-oriented system for creating binary software components that can interact. COM is the foundation technology for Microsoft's OLE (compound documents) and ActiveX (Internet-enabled components) technologies.

COM+

COM+ is an evolution of Microsoft Component Object Model (COM) and Microsoft Transaction Server (MTS). COM+ builds on and extends applications written using COM, MTS, and other COM-based technologies. COM+ handles many of the resource management tasks that you previously had to program yourself, such as thread allocation and security. COM+ also makes your applications more scalable by providing thread pooling, object pooling, and just-in-time object activation. COM+ also helps protect the integrity of your data by providing transaction support, even if a transaction spans multiple databases over a network.

Distributed Transaction Coordinator

Guide and reference documentation for system administrators and developers using the Distributed Transaction Coordinator (DTC).