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Introduction to COM and ATL 

This section provides a brief introduction to COM and ATL.

In This Section

Introduction to COM

Provides an overview of the Component Object Model's (COM) fundamental concepts, including interfaces, IUnknown, reference counting, QueryInterface, marshaling, and aggregation.

Introduction to ATL

Discusses, briefly, what the Active Template Library (ATL) was designed for, template libraries, and ATL version numbers. Includes recommendations for choosing between ATL and MFC.

Related Sections

The Component Object Model

The Platform SDK material on COM.


Provides links to conceptual topics on how to program using the Active Template Library.

ATL Class Overview

Provides reference information and links to the ATL classes.