A client can reside on the same computer as the Microsoft Exchange Server, or it can reside exclusively on the user's workstation. Client applications, designed by users to expand the capabilities of Microsoft Exchange Server, employ Microsoft Exchange Server services, but offer no services of their own. A client interacts with Microsoft Exchange Server through MAPI. The significant components of Microsoft Exchange Client are the Microsoft Exchange Client, the Microsoft Exchange Client extensions, the client application, and MAPI.
The following diagram shows a typical arrangement of Microsoft Exchange Client components on a user's workstation.
For detailed information about Microsoft Exchange Client components, see the Microsoft Exchange Server documentation in the "Database and Messaging Services" section of the Microsoft Platform SDK.