A projection technique in which the projector is positioned behind an opaque or translucent screen, projecting the image toward the audience from the rear. This method allows the subject or scene to be placed in front of the screen while still appearing illuminated by the projected image, making it commonly used in film, television, and stage productions to create the illusion of backgrounds or moving scenes. Back projection is especially useful for simulating moving environments, such as vehicles in motion, without needing on-location shooting, and it helps control lighting and perspective in a controlled studio setting.