This is a copy of a movie that is usually unfinished. A workprint may not have some of the special effects on the video stream or sound effects. It may also have several minutes missing or sometimes scenes that wont appear in the finished movie. Workprints come straight from the studio so the studio will more than likely have a watermark on there claiming the movie as their property. Some of the movie may appear in black and white or have reel change countdowns. Workprints sometimes leak onto the net in VCD format. The quality varies. Some examples are Hulk which was terrible quality and was missing many special effects and Kill Bill Vol. 1 which had good quality, but had reel change countdowns throughout the movie.