Were you ever inquisitive about how special effects in films are made? How do movie makers recreate the mystical world of Hogwarts or conjure a pre-historic earth? How do movie makers blend CGI with real life action shots? All of these motion picture miracles have been made feasible by the green screen. It is also recognised as chroma key, blue display, and color separation overlay (CSO). Minus the green screen LA technology, which is applied in studios all around the wonderful city of Los Angeles (Chroma Key technology) several remarkable motion pictures could not be developed. Moviegoers will be stuck with dull movies with poor, little, or no visual effects at all. With no chroma key, several opportunities in movie-making will still be in the desires and creativeness of film makers.