The ZERO candy bar, introduced in 1920, is a candy bar composed of a combination of caramel, peanut and almond nougat covered with a layer of white fudge (a.k.a. white chocolate fudge). Its outwardly white color, an unusual color for a candy bar, has become its trademark.
ZERO was first launched by the Hollywood Brands candy company of Minneapolis, Minnesota, in 1920 as the Double Zero Bar and was renamed "ZERO" in 1934. It is said the name "double" zero was implied to suggest the zero bar was "cool", as in low in temperature.  Initial manufacturing of the candy bar began at its factory in Centralia, Illinois, and continued through many acquisitions of the company. 
Hollywood Brands was first sold to Consolidated Foods Corporation in 1967 (which later became Sara Lee) and production continued after a fire destroyed the Centralia plant in 1980. A new production facility opened in 1983, and in 1988 Hollywood Brands was purchased by Huhtamaki Oy of Helsinki, Finland and became part of Leaf, Inc.