General

Computer is an electronic device which is capable of receiving information (data) in a particular form and of performing a sequence of operations in accordance with a predetermined but variable set of procedural instructions (program) to produce a result in the form of information or signals.

The display resolution of a digital televisioncomputer monitor or display device is the number of distinct pixels in each dimension that can be displayed. or screen sizes (typically in inches, measured on the diagonal).

It is usually quoted as width × height, with the units in pixels: for example, "1024 × 768" means the width is 1024 pixels and the height is 768 pixels. This example would normally be spoken as "ten twenty-four by seven sixty-eight" or "ten twenty-four by seven six eight".

 

Resolution

Refers to the sharpness and clarity of an image. The term is most often used to describe monitors, printers, and bit-mapped graphic images. In the case of dot-matrix and laser printers, the resolution indicates the number of dots per inch. For example, a 300-dpi (dots per inch) printer is one that is capable of printing 300 distinct dots in a line 1 inch long. This means it can print 90,000 dots per square inch.

For graphics monitors, the screen resolution signifies the number of dots (pixels) on the entire screen. For example, a 640-by-480 pixel screen is capable of displaying 640 distinct dots on each of 480 lines, or about 300,000 pixels. This translates into different dpi measurements depending on the size of the screen. For example, a 15-inch VGA monitor (640x480) displays about 50 dots per inch.

 

Printers, monitors, scanners, and other I/O devices are often classified as high resolution, medium resolution, or low resolution. The actual resolution ranges for each of these grades is constantly shifting as the technology improves.

 

Pixel

Short for Picture Element, a pixel is a single point in a graphic image. Graphics monitors display pictures by dividing the display screen into thousands (or millions) of pixels, arranged in rows and columns. The pixels are so close together that they appear connected.

The number of bits used to represent each pixel determines how many colours or shades of Gray can be displayed. For example, in 8-bit colour mode, the colour monitor uses 8 bits for each pixel, making it possible to display 2 to the 8th power (256) different colours or shades of Gray.

 

On colour monitors, each pixel is actually composed of three dots -- a red, a blue, and a green one. Ideally, the three dots should all converge at the same point, but all monitors have some convergence error that can make colour pixels appear fuzzy. The quality of a display system largely depends on its resolution, how many pixels it can display, and how many bits are used to represent each pixel. VGA systems display 640 by 480, or about 300,000 pixels. In contrast, SVGA systems display 800 by 600, or 480,000 pixels. True Colour systems use 24 bits per pixel, allowing them to display more than 16 million different colours.

PPI

It means pixels per inch, a measurement of how a monitor displays an image. The resolution of an image displayed on a monitor is determined by its ppi, or the number of pixels contained within one square inch of monitor space.

 

MegaPixel

One million pixels. The term is used in reference to the resolution of a graphics device, such as a scanner, digital camera or monitor.

 

Most common display resolutions in the first half of 2014
AcronymAspect ratioWidth (px)Height (px) % of Steam users % of web users
SVGA 4:3 800 600 00.08 00.64
WSVGA ~17:10 1024 600 00.17 01.59
XGA 4:3 1024 768 02.85 09.84
XGA+ 4:3 1152 864 00.34 00.85
WXGA 16:9 1280 720 00.93 01.65
WXGA 5:3 1280 768 00.52 01.09
WXGA 16:10 1280 800 02.44 08.90
SXGA– (UVGA) 4:3 1280 960 00.35 00.48
SXGA 5:4 1280 1024 07.05 05.74
HD ~16:9 1360 768 03.00 02.43
HD ~16:9 1366 768 24.53 26.64
SXGA+ 4:3 1400 1050 00.10 n/a
WXGA+ 16:10 1440 900 05.74 05.95
HD+ 16:9 1600 900 07.76 04.99
UXGA 4:3 1600 1200 00.30 n/a
WSXGA+ 16:10 1680 1050 06.27 02.96
FHD 16:9 1920 1080 32.91 08.64
WUXGA 16:10 1920 1200 02.11 00.95
QWXGA 16:9 2048 1152 00.08 n/a
WQHD 16:9 2560 1440 00.93 00.58
WQXGA 16:10 2560 1600 00.13 n/a

 

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