From a technical standpoint, a movie is a sequence of photographic images taken with a camera, and presented through a film projector, using an image replacement rate greater than 18 frames per second, so it creates in the human eye the illusion of continuity with no delay between each frame due to the persistence of vision.
Movies is a collection that provides high quality icons that represent a motion picture reel. The set is ideal for use in video editing software, best suited for video playback programs like Quicktime itself, or to the folders where movies are usually saved.
To learn mode about changing your default Mac OS X icons you can access the Apple Support page HERE.
