A webcam is a video camera that feeds or streams its image in real time to or through a computer to a computer network.
When "captured" by the computer, the video stream may be saved, viewed or sent on to other networks via systems such as the internet, and emailed as an attachment.
Video features, including faces, shapes, models and colors can be observed and tracked to produce a corresponding form of control.
For example, the position of a single light source can be tracked and used to emulate a mouse pointer, a head-mounted light would enable hands-free computing and would greatly improve computer accessibility.
With very-low-light capability, a few specific models of webcams are very popular to photograph the night sky by astronomers and astro photographers.
Mostly, these are manual-focus cameras and contain an old CCD array instead of comparatively newer CMOS array.
The Eye Toy for the Play Station 2, Play Station Eye for the Play Station 3, and the Xbox Live Vision camera and Kinect motion sensor for the Xbox 360 and are color digital cameras that have been used as control input devices by some games.
The most popular use of webcams is the establishment of video links, permitting computers to act as videophones or videoconference stations.Unauthorized access of webcams can present significant privacy issues (see "Privacy" section below).In December 2011, Russia announced that 290,000 Webcams would be installed in 90,000 polling stations to monitor the Russian presidential election, 2012.Webcam features and performance can vary by program, computer operating system, and also by the computer's processor capabilities.Video calling support has also been added to several popular instant messaging programs. Software is available to allow PC-connected cameras to watch for movement and sound, a computer e-mailed images of the burglar during the theft of the computer, enabling the owner to give police a clear picture of the burglar's face even after the computer had been stolen.