Projectors may be used for various applications. Small projectors are used for business presentations in boardroom settings, but projectors may also be used to display films through a home theatre entertainment system. Cinema complexes use large, powerful projectors to show movies and this type of large projector may also be used at other live events. The smallest, handheld projectors are also called pocket projectors.

Projectors may be used in the following applications:

  • Entertainment venues and ceremonies
  • Theatrical presentations and visual effects for music events
  • Projection of video material and the words of songs in houses of worship
  • Cinemas and film festivals
  • Projection of presentations at corporate events and conferences
  • Home cinema applications
  • Educational classroom presentations
  • Some projectors are mounted inside rear-projection television sets

Projectors are available in different resolutions. A higher resolution means a better picture quality and a higher price tag. A resolution of 1920x1080 is considered a very good. More common are the VGA (800x600) and XGA (1024x768) projectors. Another projector specification is the output of its light source (measured in lumens). Projectors with a light output of less than 2500 lumens are more suited to venues with small screens and subdued ambient lighting. For a large boardroom with a lot of ambient light, a projector with a light output of about 4000 lumens or more may be required.

Several technologies are used in projectors. The most common is the LCD projector, which uses liquid crystal display light gates. LED projectors use an array of light-emitting diodes and CRT projectors use cathode ray tubes, as in the tube of a traditional television set.