Pixel

The term “pixel”, or picture element, is not only used in photography. As the name says, a pixel is the smallest element of a picture, just like a letter is the smallest element of a word. It is used to define the resolution of a screen or a digital camera sensor.

The color of each pixel in RGB mode is defined by a combination of the values from 3 channels, the Red one, the Green one and the Blue one. The value is between 0 and 255. For example:

A red pixel has these values: R=255 G=0 B=0