Form describes the external plastic shape. It conveys the visual, aesthetic, and symbolic aspects of a product.
It is the opposite of function, which for example has to take into consideration ergonomic aspects, user-friendliness, and safety. Product design is always a negotiation between the two poles of form and function, which form an inseparable unity. Depending on the aims, trends, and the motivation and working methods of the product designer, either functionality (e.g. Bauhaus and the Ulm School of Design) or form (e.g. Memphis) may be given greater emphasis. For a long time, the design principle that “form follows function” was viewed as a generally accepted rule. However, since the 1970s, it has been joined by such variations as “form follows fun”, “form follows emotion”, or “form follows fiction”.