(2) A software program that extends the capabilities of larger programs. For example, there are many Excel add-ins designed to complement the basic functionality offered by Excel. In the Windows environment, add-ins are becoming increasingly common thanks to OLE 2.0.
(3) In Windows Home Server, add-in refers specifically to the supplemental programs that users can install to extend the capabilities of the Windows Home Server program. Most add-ins are third party or community developed.



