computer terminal, a device that enables a computer to receive or deliver data. Computer terminals vary greatly depending on the format of the data they handle. For example, a simple early terminal comprised a typewriter keyboard for input and a typewriter printing element for alphanumeric output. A more recent variation includes the keyboard for input and a televisionlike screen to display the output. Liquid crystal displays, cathode-ray tubes, and gas plasma panels (the last involving an ionized gas, sandwiched between glass layers, which glows to form dots which, in turn, connect to form lines) have been used as display screens. Such displays can present a variety of output, ranging from simple alphanumerics to complex graphic images used as design tools by architects and engineers. Portable terminals typically use liquid crystal displays because of their low power requirements. The terminals of pen-based computers use a stylus to input handwriting on the screen. Touch-sensitive terminals accept input made by touching a pressure-sensitive panel in front of a menu displayed on the screen. Other familiar types of terminals include store checkout systems that deliver detailed printed receipts and use laser scanners to read the barcodes on packages, and automatic teller machines in banks.
See L. Tijerina, Video Display Terminal Workstation Ergonomics (1984).
The Columbia Electronic Encyclopedia, 6th ed. Copyright © 2012, Columbia University Press. All rights reserved.
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