Imagine having hi-fi music and great HD video in every room of your home with nothing more than an elegant wall mounted keypad and virtually invisible in-wall or in-ceiling speakers showing. This is the dream system of interior decorators and homeowners alike due to the lack of components and clutter.
Distributed audio/video refers to a centralized system that pipes music and video signals throughout the home. Because the system is centralized, the only components present in each room are speakers and TV screens. Control of the system is made through a handheld remote or wall mounted control panels. The centralized components can either be hidden away in a cabinet, or if you prefer, mounted in an impressive rack system array in a closet.
Original information from http://www.smarthome.com/wwaudvid.html