A video display unit (VDU) consists of: A computer output device that uses a cathode ray tube or other technology to present visual images, one or more input devices, such as a keyboard, a mouse, or both. A synonym sometimes used in the United States is video display terminal (VDT). VDU seems to predominate elsewhere. The term is widely used in ergonomic discussions, guidelines, and standards related to Website Designers safety and efficiency. The "classic" VDU is the desktop display and keyboard. However, as personal computers and workstations become more portable and smaller in size, the safety and design guidelines for VDUs call for continuing reconsideration.
The term display mode refers to the characteristics of a computer display, in particular the maximum number of colours and the maximum image resolution (in pixels horizontally by pixels vertically). There are several display modes that can be found in personal computer (PC) systems today. The earliest displays for personal computers were monochrome monitors that were used in word processors and text-based computer systems in the 1970s. In 1981, IBM introduced the Color Graphics Adapter (CGA). This display system was capable of rendering four colors, and had a maximum resolution of 320 pixels horizontally by 200 pixels vertically. While CGA was all right for simple computer games such as solitaire and checkers, it did not offer sufficient image resolution for extended sessions of word processing, desktop publishing, or sophisticated graphics applications.
In 1984, IBM introduced the Enhanced Graphics Adapter (EGA) display. It allowed up to 16 different colors and offered resolution of up to 640 x 350. This improved the appearance over earlier displays, and made it possible to read text easily. Nevertheless, EGA did not offer sufficient image resolution for high-level applications such as graphic design and desktop publishing. This mode has become essentially obsolete, although it is sometimes found in old word processors and PCs in private homes. In 1987, IBM introduced the Video Graphics Array (VGA) display system. This has become the accepted minimum standard for PCs. Some VGA monitors are still in use today. The maximum resolution depends on the number of colors displayed. You can choose between 16 colors at 640 x 480, or 256 colors at 320 x 200. All IBM-compatible computers support the VGA standard.
The term display mode refers to the characteristics of a computer display, in particular the maximum number of colours and the maximum image resolution (in pixels horizontally by pixels vertically). There are several display modes that can be found in personal computer (PC) systems today. The earliest displays for personal computers were monochrome monitors that were used in word processors and text-based computer systems in the 1970s. In 1981, IBM introduced the Color Graphics Adapter (CGA). This display system was capable of rendering four colors, and had a maximum resolution of 320 pixels horizontally by 200 pixels vertically. While CGA was all right for simple computer games such as solitaire and checkers, it did not offer sufficient image resolution for extended sessions of word processing, desktop publishing, or sophisticated graphics applications.
In 1984, IBM introduced the Enhanced Graphics Adapter (EGA) display. It allowed up to 16 different colors and offered resolution of up to 640 x 350. This improved the appearance over earlier displays, and made it possible to read text easily. Nevertheless, EGA did not offer sufficient image resolution for high-level applications such as graphic design and desktop publishing. This mode has become essentially obsolete, although it is sometimes found in old word processors and PCs in private homes. In 1987, IBM introduced the Video Graphics Array (VGA) display system. This has become the accepted minimum standard for PCs. Some VGA monitors are still in use today. The maximum resolution depends on the number of colors displayed. You can choose between 16 colors at 640 x 480, or 256 colors at 320 x 200. All IBM-compatible computers support the VGA standard.