One of the most recognizable elements of Play-Doh is its smell and Hasbro, the well-known company in fact registered its perfume, thus becoming one of the 13 companies to have registered a "sensory brand", ie a brand characterized by physics like sounds, colors or perfumes that a company can use for its products. From the point of view of the "consumer" the fragrance of the product, (and not only) is associated exclusively with the product of this particular company. The famous modeling paste was invented in 1956. It was presented in a fair dedicated to education and was immediately commercialized, enjoying a success that still today passes from one generation of children to another. The characteristic smell of the modelling paste has remained unchanged over the years, here is the registered description of the USPTO (US Patent and Trademark Office): "Sweet, slightly musky.Vanilla-like. Slight overtones of cherry. Natural smell of a salted, wheat- based dough" By registering the scent of Play-Doh, Hasbro believes that there is no risk of confusion with similar products on the market.