COM

Component Object Model (COM) is a Microsoft centric interface standard for software componentry introduced by Microsoft in 1993. It is used to enable interprocess communication and dynamic object creation in any programming language that supports the technology.  The term COM is often used in software development industry as an umbrella term that encompasses the OLE,OLE Automation, COM+ and DCOM technologies.

Please refer to the below link for further details.

http://msdn.microsoft.com/en-us/library/ms809980.aspx.