A webcam is a video capture device that is connected to a computer or computer network, often using a USB port or, if connected to a network, ethernet or Wi-Fi.
The most popular use is for videotelephony, permitting a computer to act as a videophone or video conferencing station. This can be used in messenger programs such as Windows Live Messenger, Skype and Yahoo! messenger services. Other popular uses, which include the recording of video files or even still-images, are accessible via numerous software programs, applications and devices.
Webcams are known for low manufacturing costs and flexibility,making them the lowest cost form of videotelephony.
The term 'webcam' may also be used in its original sense of a video camera connected to the Web continuously for an indefinite time, rather than for a particular session, generally supplying a view for anyone who visits its web page over the Internet. Some of these, for example those used as online traffic cameras, are expensive, rugged professional video cameras.
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