(1) A component you can add to a
computer or other
device to increase its capabilities. Add-ins can increase
memory or add
graphics or
communications capabilities to a computer. They can come in the form of
expansion boards,
cartridges, or
chips. The term
add-in is often used instead of
add-on for chips you add to a
board that is already installed in a computer. In contrast,
add-on almost always refers to an entire
circuit board.
(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.
