All moving objects possess six degrees of freedom – three linear and three rotary. The task of a linear motion guideway is to eliminate, as closely as possible, five of these degrees of freedom, leaving a single rotary or linear axis of motion. Air bearings are the purest and highest performance means of defining linear or rotary motion, and have substantial advantages over conventional mechani...

History of Film The history of film is the historical development of the medium known variously as cinema, motion pictures, film, or the movies. The history of film spans over a hundred years, from the latter part of the 19th century to the present day. Motion pictures developed gradually from a carnival novelty to one of the most important tools of communication and entertainment, and mass med...