‘Pixel’ is short for Picture Element. When we see graphic images on digital devices the display divides the screen into thousands or millions of pixels, arranged in rows and columns. Each pixel has its own address in this grid and is represented by dots or squares. Pixels build up a sample of an original image and are the smallest component of a digital image. The more pixels used to represent an image, the closer it will resemble the original.
The number of pixels used to create an image is often referred to as the ‘resolution’. The best digital cameras have the highest pixel count because they produce a higher-quality image. In colour images a pixel is typically comprised of three of four colour dots – a red, a blue and a green. When these colour dots converge, they build coloured pixels. You might have spent most of your youth playing Mario games with 256 x 224 pixels – now a typical HD monitor can display 1,366 x 768 pixels.
Damien Arness-Dalton, Science Museum