What is "addons"

Usage examples of "addons".

Plan-ahead addons were cheap, but he had convinced her that they made stupid mistakes of their own.

In good lighting it was beautiful, its tricolored bulk looming like the Great Wall of China amid a tasteful selection of addons, which included four input desks, several banks of additional memory, and two sixbysixfoot color monitors capable of forming the most exacting of projections.