Precedent is also described as "the unique knowledge embedded in a known design" $($Oxman$,1994,$ p$.146),$ meaning, in everyday terms, that the memory of having experienced an existing design is a memory that contains special forms of knowledge... At heart, the design case is a description of a real artifact or experience that has been intentionally designed. A case may be as minimal as an individual image of a commercial product, a building, an advertisement, a classroom or anything else designed; these forms of design cases appear in hundreds of magazines, design annuals, competition catalogs, display books, web portfolios and similar venues.

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