VGA XGA SXGA UXGA WXGA WSXGA WUXGA

Resolution is a term often used interchangeably with addressability, but it more properly refers to the sharpness, or detail, of the visual image. It is primarily a function of the monitor and is determined by the beam size and dot pitch (sometimes referred to as "line pitch"). An image is created when a beam of electrons strikes phosphors which coat the base of the monitor's "screen. A group comprising one red, one green and one blue phosphor is known as a pixel. A pixel represents the smallest piece of the screen that can be controlled individually, and each pixel can be set to a different color and intensity. A complete screen image is composed of thousands of pixels and the screen's resolution - specified in terms of a row by column figure - is the maximum number of displayable pixels. The higher the resolution, the more pixels that can be displayed and therefore the more information the screen can display at any given time. Resolutions generally fall into predefined sets and the table below shows the series of video standards since CGA, the first to support color/graphics capability:
 

The lack of a widely accepted standard for VGA pixel addressabilities was a problem for manufacturers, system builders, programmers and end users alike. The matter was addressed by the Video Electronics Standards Association (VESA) - a consortium of video adapter and monitor manufacturers whose goal is to standardize video protocols - who developed a family of video standards that were backward compatible with VGA but offered greater resolution and more colors. For a while - prior to the emergence of the "XGA" family of definitions - VESA's VGA BIOS Extensions (collectively known as Super VGA) were the closest thing to a standard.

WXGA  16:9 or 16:10 Ratio

XGA  4:3 Ratio

Typically, an SVGA display can support a palette of up to 16.7 million colors, although the amount of video memory in a particular computer may limit the actual number of displayed colors to something less than that. Image-resolution specifications vary. In general, the larger the diagonal screen measure of an SVGA monitor, the more pixels it can display horizontally and vertically. Small SVGA monitors (14in diagonal) usually use a resolution of 800x600 and the largest (20in+ diagonal) can display 1280x1024, or even 1600x1200, pixels.

XGA was developed by IBM and was originally used to describe proprietary graphics adapters designed for use in Micro Channel Architecture expansion slots. It has subsequently become the standard used to describe cards and displays capable of displaying resolutions up to 1024x768 pixels.

VESA's SXGA standard is used to describe the next screen size up - 1280x1024. SXGA is notable in that its standard ratio is 5:4, while VGA, SVGA, XGA and UXGA are all the traditional 4:3 aspect ratio found on the majority of computer monitors.

Pixels are smaller at higher resolutions and prior to Windows 95 - and the introduction of scaleable screen objects - Windows icons and title bars were always the same number of pixels in size whatever the resolution. Consequently, the higher the screen resolution, the smaller these objects appeared - with the result that higher resolutions worked much better on physically larger monitors where the pixels are correspondingly larger. These days the ability to scale Windows objects - coupled with the option to use smaller or larger fonts - affords the use far greater flexibility, making it perfectly possible to use many 15in monitors at screen resolutions of up to 1024x768 pixels and 17in monitors at resolutions up to 1600x1200.

SVGA standards support the display of 16 million colors, but the number of colors that can be displayed simultaneously is limited by the amount of video memory installed in a system. The greater number of colors, or the higher the resolution or, the more video memory will be required. However, since it is a shared resource reducing one will allow an increase in the other.

WXGA resolution can vary depending on the size of the screen. WXGA basically means wide screen, the aspect ratio is 16:9 or 16:10 versus the more box like 4:3 aspect ratio of a standard laptop. If you're a movie fanatic who wishes you could watch that great DVD collection while on the road/plane/lunch break then you may want to take a look at laptop computers with this type of screen. There are variations on this such as WSXGA or WUXGA which are wide screen versions of the higher resolution modes.

UXGA resolution of 1600x1200. This is featured on mainly high end laptops which have medium to large screens (15.4 inch or greater). Like SXGA+ this resolution is great for when you need to see more of the screen at once such as with spreadsheets or editing large photos, etc.

WSXGA is a resolution that supports 1600 by 900 pixels or 1680 x 1050 pixels.

WUXGA supports 1920 by 1200 pixels.

TFT Thin Film Transistor, also referred to as active matrix or even used at the same time such as “TFT Active Matrix LCD!”. You would be hard pressed to find a modern laptop that doesn't use this type of screen, it has become the standard for bright and colorful screens, although “bright” and “colorful” may vary from each manufacturer.

LCD Liquid Crystal Display. LCD's are found in countless gadgets that require a small or flat screens such as cell phones, handheld game systems, computer monitors, etc.