It then uses the values stored in the digital photograph to specify the brightness and color of each pixel in this grid-a form of painting by number. Controlling, or addressing a grid of individual pixels in this way is called bit mapping and digital images are called bit-maps. Here you see a portrait of Amelia Earhart done entirely in jelly beans. Think of each jelly bean as a pixel and it's easy to see how dots can form images. Herman Goelitz Candy Company Inc. Makers of Jelly Belly jelly beans.
More pixels add detail and sharpen edges.
If you enlarge any digital image enough, the pixels will begin to show-an effect called pixelization. This is not unlike traditional silver-based prints where grain begins to show when prints are enlarged past a certain point. The more pixels there are in an image, the more it can be enlarged before pixelization occurs. Each pixel is a small square made up of a single color. The size of a photograph is specified in one of two ways-by its dimensions in pixels or by the total number of pixels it contains.