video display terminal

computer technology

Also known as: VDT

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The Information Architects of Encyclopaedia Britannica

Last updated

June 17, 2026

Quick Summary

A video display terminal (VDT), also known as a visual display unit (VDU), is a computer peripheral that displays information visually. It acts as an interface, transforming computer-stored data into a format humans can see.123

The primary function of a VDT is to present information, typically as text or images, on a screen. Early VDTs used cathode-ray tube (CRT) technology, where electron beams created images on a phosphorus-coated surface. More modern VDTs utilize flat-panel displays, such as liquid crystal or light-emitting diodes. These advanced systems allow for features like scrolling, multiple windows, and even touch-screen interaction, enhancing the user's ability to interact with digital information.3

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computerized typesetting
Some systems have a video display terminal (VDT), consisting of a keyboard and a CRT viewing screen, that enables the operator to see and correct the words as they are being typed. If a system has a line printer, it can produce printouts of “hard copy.”
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Some systems have a video display terminal (VDT), consisting of a keyboard and a CRT viewing screen, that enables the operator to see and correct the words as they are being typed. If a system has a line printer, it can produce printouts of “hard copy.”
Read More

information processing
Video
Possibly the most widely used video display device, at least in the industrialized world, is the television set. Designed primarily for video and sound, its image resolution is inadequate for alphanumeric data except in relatively small amounts. Use of the television set in text-oriented information systems has been limited to…
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Possibly the most widely used video display device, at least in the industrialized world, is the television set. Designed primarily for video and sound, its image resolution is inadequate for alphanumeric data except in relatively small amounts. Use of the television set in text-oriented information systems has been limited to…
Read More

peripheral device
Output equipment includes video display terminals, ink-jet and laser printers, loudspeakers, headphones, and devices such as flow valves that control machinery, often in response to computer processing of sensor input data. Some devices, such as video display terminals and USB hubs, may provide both input and output. Other…
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Output equipment includes video display terminals, ink-jet and laser printers, loudspeakers, headphones, and devices such as flow valves that control machinery, often in response to computer processing of sensor input data. Some devices, such as video display terminals and USB hubs, may provide both input and output. Other…
Read More