Many people have heard of VGA in one form or another has it has been the standard when talking about graphics displays on digital devices for years. VGA stands for Video Graphics Array and was developed by IBM for its early displays. This array contains the information about the colours to display and in what part of the screen to show it.
While this was fine when it was developed it soon became apparent as computer user’s needs grew that it wouldn’t hold enough data to allow the viewing of high quality images. This has lead over the years to the original standard being developed into a number of different styles that allow different amounts of information to be displayed on the users display.
The amount of information that can be carried in the array allows the display of more pixels the more pixels you can display the more clearer and crisper the image will look. As technology has progressed people want more and more from there displays with better looking games and movies at higher resolutions.
Some of the display standards that have evolved over the years are:
XGA: This was the next step and is still used today for displaying images on many digital cameras and other small devices that need crisp and clear images at small resolutions. Things such as mobile phones and hand held gaming devices for example make use of a XGA displays. Allowing the use of more colours than was previously used, and using more pixels, but still nothing like modern computers use nowadays. It allows 800×600 displays at 16bit colour or 1024×768 display with 256 colours.
SVGA: Developed as an extension or update of the original VGA display to allow the use of far better display equipment on their PC’s. Originally to allow the use of true colour 32 bit displays but now the SVGA standard is continually being improved to allow for the fast advancements in display technology.
There are other acronyms used to talk about different displays especially with laptops and other portable devices. But the main ones are the ones that are talked about above.
Other terms used to describe VGA are:
Resolution: used to describe the size of displays in pixels for example a 800×600 display is 800 pixels wide and 600 pixels in height.
Pixel: a small dot on the screen the size of these dots is related to how clear the image appears. It can be any combination of colours.
Colour depth is measured using a number of terms these are normally mentioned as “bits” and describe the amount of colours that a pixel can contain. 16 and 32 bit are common place wit. 16 bit can contain up to 65,536 colours with a true 32 bit display capable of displaying 4.2 billion. Although true 32 bit systems are available they are very rare. Most displays that say 32 bit are actually 24 bit with a couple of extra features. 24 bit displays are capable of showing 16,777,216 and are probably the most common at this time and with over 16million colour combinations are more than enough for the human eye.
