Component Object Model (COM) - Win32 apps
By stevewhims
Archived: 2026-04-05 23:38:38 UTC
In this article
1. Purpose
2. Where applicable
3. Run-time requirements
4. In this section
5. Related documentation
6. Related topics
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 objects can be created with a variety of programming languages. Object-oriented languages, such as C++,
provide programming mechanisms that simplify the implementation of COM objects. These objects can be within
a single process, in other processes, even on remote computers.
For information on which operating systems are required to use a particular interface or function, see the
Requirements section of the documentation for the interface or function.
Topic Description
COM Fundamentals Describes the fundamental concepts and programming reference.
OLE and Data
Transfer
Describes compound documents and data transfer.
Controls and Property
Pages
Describes ActiveX controls and property pages.
COM Language
Translations
Describes the differences between programming languages and describe how to
translate COM object syntax from one language to another.
Topic Description
COM Fundamentals Describes the fundamental concepts and programming reference.
OLE and Data
Transfer
Describes compound documents and data transfer.
https://msdn.microsoft.com/library/windows/desktop/ms680573.aspx
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Topic Description
Controls and Property
Pages
Describes ActiveX controls and property pages.
COM Language
Translations
Describes the differences between programming languages and describe how to
translate COM object syntax from one language to another.
Topic Description
Component
Object Model
(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.
Automation
Automation enables software packages to expose their unique features to scripting tools
and other applications. Automation uses the Component Object Model (COM), but may
be implemented independently from other OLE features, such as in-place activation.
Microsoft
Interface
Definition
Language
(MIDL)
The Microsoft Interface Definition Language (MIDL) defines interfaces between client
and server programs. Microsoft includes the MIDL compiler with the Platform Software
Development Kit (SDK) to enable developers to create the interface definition language
(IDL) files and application configuration files (ACF) required for remote procedure call
(RPC) interfaces and COM/DCOM interfaces. MIDL also supports the generation of
type libraries for OLE Automation.
Structured
Storage
Structured Storage provides file and data persistence in COM by handling a single file as
a structured collection of objects known as storages and streams.
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.
Additional resources
Training
Last updated on 08/21/2020
Source: https://msdn.microsoft.com/library/windows/desktop/ms680573.aspx
https://msdn.microsoft.com/library/windows/desktop/ms680573.aspx
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