Video Graphics Array (VGA) is a computer display standard first marketed in 1987 by IBM. VGA belongs to a family of earlier IBM video standards and largely remains backward compatible with them. VGA can be seen as an enhancement of and successor to the previous EGA and CGA graphics adapters. MCGA, also produced by IBM, is a simpler version of the VGA hardware.
SVGA was extended from VGA, defined by Video Electronics Standards Association instead of IBM.
VGA is referred to as an "array" instead of an "adapter" because it was implemented from the start as a single chip (a gate array), replacing the Motorola 6845 and a full-length ISA board full of discrete components that the MDA, CGA, and EGA used. This also allowed it to be placed directly on a PC's motherboard with a minimum of difficulty (it only required video memory, timing crystals and an external RAMDAC), and the first PS/2 models were equipped with VGA on the motherboard. Since it wasn't restricted to being an add-on board, the name refers to the chip itself.
As with most IBM hardware the VGA was extensively cloned by other manufacturers. While the VGA in its original form has been obsolete for some time, it was the last IBM standard that the majority of PC clone manufacturers decided to follow, making it the only standard graphics interface that can be relied on to be present on the PC architecture. VGA was technically superseded by IBM's XGA standard, but in reality it was superseded by the numerous extensions to VGA by clone manufacturers that came to be known as Super VGA.
VGA remains a relevant graphics standard. It forms the "lowest common denominator" that all PC graphics cards need to support prior to a device-specific driver being loaded. On Windows machines, the Microsoft Windows splash screen appears while the machine is still operating in VGA mode, which is the reason that this screen always appears in reduced resolution and color depth compared to following screens.
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