Scope of ATL

ATL allows you to easily create COM objects, Automation servers, and ActiveX controls. ATL provides built-in support for many of the fundamental COM interfaces.

ATL is shipped as source code which you include in your application. ATL also makes a DLL available (atl90.dll), which contains code that can be shared across components. However, this DLL is not necessary.

See also

Introduction to ATL
ATL Project Wizard