Actual Photo Pixels In A Viewable Size
The image on the left is a screen capture of a portion of the mountain scene image from the introduction page that has been magnified 6 times larger than the normal 72 to 90 ppi computer monitor resolution. In this representation you can just begin to see the actual square pixels of different colors that make up the digital image. The square pixels are even more visible at 12 times magnification in the image in the example in the middle where you can see that each pixel is a single solid color. Using the example on the right you can see that color shading in an image is accomplished by changing the color of each individual pixel.

Each pixel is solid color

20X30 pixel blue to white gradient at actual size

Same image as above but magnified 7X.
Pixels are solid colors but give the illusion of smooth color blending in an image when viewed at normal resolution