A product design specification (PDS) is a statement of how a design is made (specify the design), what it is intended to do, and how far it complies with the requirements. Requirements may be gathered in the Product Requirement Specification (PRS). Its aim is to ensure that the subsequent design and development of a product meets the needs (or requirements) of the user. Product design specification is one of the elements of product lifecycle management.
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Product design specification Wikipedia(Text) CC BY-SA