A projector is device that projects an image, presentation or video onto a surface, mainly used a projector screen. Most projectors create an image by shining a light through a small transparent lens, but some newer types of projectors can project the image directly, by using lasers.

The very common type of projector used is called a video projector. Video projectors are digital replacements for older types of projectors such as slide projector and overhead projector. These earlier types of projectors were mostly replaced with digital video projectors throughout the 1990s and early 2000s, but old analog projectors are still used at some places. The newest types of projectors are portable that use lasers or leds to project images. Their projections are hard to see if there is too much ambient light.