Definition (1):
A product system is a group of diverse but related items that function in a compatible manner. For example, the extensive iPod product system includes headphones and headsets, cables and docks, armbands, cases, power, and car accessories, and speakers.
Definition (2):
“A product system is a collection of unit processes connected by flows of intermediate products which perform one or more defined functions.” A description of this system consists of unit processes, product flows, and elementary flows along the system boundaries, and in-between product flows within this system.
Definition (3):
It is the highest degree system that is designed, the total intervention for addressing the design problem. The total product system boundary is the system boundary describing the control limit. It is something special because only one system boundary exists for a given design or project intervention. Identifying this system defines the boundary along which you need to put up inputs and send outputs that this intervention produces and also defines your control’s scope over the overall project.
This system is a combination of material products required together to fulfill the needs of a user. A microwave oven and ovenproof cooking bowls can also build up a product system.