Prototyping serves to provide specifications for a real, working system rather than a theoretical one. In some workflow models, creating a prototype (a process sometimes called materialization) is the step between the formalization and the evaluation of an idea. A User Experience Prototype captures enough aspects of the intended design that it can support user research. 2  A Visual Prototype captures the size and appearance, but not the functionality, of the intended design.
In the mid-1930s, the last main improvement to the leather football helmet was introduced: The facemask. Vern McMillan, who owned a sporting goods store in Terre Haute, Indiana, was credited with inventing the first facemask design.
With the banning of spearing in 1976 and the introduction of safer helmets, the number of injuries were down: in 1997, only seven high school players and one college player were paralyzed. Nevertheless, in another recent study recording brain trauma in more than 1,200 high school athletes over a three-year period, football accounted for the greatest percentage of injuries, by far: