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Computer display standard

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Various computer display standards or display modes have been used in the history of the personal computer. They are often a combination of resolution (specified as the width and height in pixels), colour depth measured in bits, and refresh rate[?] expressed in Hertz. Until recently, all computer monitors had a 4:3 aspect ratio. Recently, monitors with 16:9 and 16:10 aspect ratios have become available, leading to new widescreen formats.

Current standards

WUXGA - Widescreen Ultra XGA: 1920 x 1200, with a 16:10 aspect ratio
UXGA[?] - Ultra XGA. A de facto standard with a resolution of 1600 x 1200 with 32 bit pixels, true colour.
SXGA[?] - Super XGA. A de facto standard with a resolution of 1280 x 1024 with 32 bit pixels, true colour.

Older standards

XGA - Extended Graphics Array is an IBM display standard introduced in 1990. XGA supports a resolution of 1024 x 768 pixels with a palette of 256 colours, or 640 x 480 with high colour (16 bits per pixel). XGA-2 added 1024 x 768 support for high colour and higher refresh rates, improved performance, and supports 1360 x 1024 in 16 colours.
SVGA - Super Video Graphics Array. A video display standard created by VESA for IBM PC compatible personal computers. The resolution is 800 x 600 4-bit pixels. Each pixel can therefore be one of 16 colours.
VGA - Video Graphics Array, with 640 x 480 pixels in 16 colours and a 4:3 aspect ratio. There is also a text mode with 720 x 400 pixels.
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EGA - Enhanced Graphics Adapter, with a resolution of 640 x 350 pixels of 16 different colours selectable via a palette.
CGA - One of IBM's earliest hardware video display standards for use in IBM PCs. CGA can display 80 x 25 or 40 x 25 text in 16 colours, 640 x 200 pixels graphics in 2 colours or 320 x 200 in 4 colors (IBM PC video modes 0-6).
Hercules, A monochrome display with resolution of 720 by 348 capable of text and graphics.
MDA, monochrome display adapter, the original standard on IBM XT[?] PCs. Supports text only at 720 by 350 pixels.