Projectors

 A data projector takes the image that displays on a computer screen and projects it onto a screen so that an audience of people can see the image clearly. For example, many classrooms use data projectors so all students easily can see an instructor's presentation on the screen. 

Data projectors can be large devices attached to a ceiling or wall in an auditorium. Some operating systems allow projectors to be part of the network, which enables a presenter to operate the projector remotely via a network connection.
 
Others, designed for the mobile user, are small portable devices.
Two types of smaller, low-cost units are LCD projectors and DLP projectors.
 
An LCD projector, using liquid crystal display technology, attachesbdirectly to a computer, and uses its own light source to display the information shown on the computer screen. 
 
A digital light processing (DLP) projector uses tiny mirrors to reflect light, which produces crisp, bright, colorful images that remain in focus and can be seen clearly even in a well-lit room.

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