Projector refers to an optical instrument which projects an image from a transparency or an opaque image onto a projection screen or other surface, using an intense light and one or more lenses to focus the image.
Projectors are used for displaying an image on a projection screen or similar surface for the view of an audience. Various kind of projectors are: video/electronic projectors, LCD projector, CRT projector, DLP projector, LCOS projector, Transparency projectors, Movie projector, Slide projector, Overhead projector, Magic Lantern Enlarger, other handheld projector, opaque projector or reflective projector, etc.