A stereoscopic film is a motion picture that creates the illusion of three-dimensional depth from two-dimensional images.
It uses a stereoscopic lens to record two separate images from slightly different perspectives, and these images are projected using a special projector with two synchronized projectors.
Viewers wear special glasses that allow each eye to see only one image, creating the illusion of depth.
Today, stereoscopic films are used primarily for entertainment, some of the most popular 3D movies including Avatar (2009) and Hugo (2011).