The smallest unit of a digitized image created by a digital device, such as a computer, camera, or scanner. Pixel is short for “picture element”.
The more pixels per inch the better the resolution. On computer monitors, the display is divided into rows and columns containing thousands or millions of pixels.
Each pixel is composed of three dots representing the three color channels of red, green, and blue light that are necessary for creating a color image on computer monitors and television screens.
Because of their small size, the pixels appear to merge, simulating a continuous tone image, but when magnified they appear to be tiny square blocks of light, as shown in the illustration below.