Like digital cameras, computer monitors (and other display devices) create everything you see on-screen out of pixels. You typically can choose from several monitor settings, each of which results in a different number of screen pixels. Here are the standard settings:
800 x 600 pixels
1024 x 768 pixels
1280 x 1024 pixels
1600 x 1200 pixels
When you display a digital photo, the monitor devotes one screen pixel to every image pixel. For example, this image shows a monitor with the screen resolution set to 1600 x 1200. The flower photo has a resolution of 800 x 600 pixels — and therefore consumes 800 of the available 1600 horizontal screen pixels and 600 of the 1200 vertical pixels.
Pixel count has no effect on the quality of onscreen pictures; it only determines display size. Even the most inexpensive digital camera captures enough pixels to cover a large expanse of on-screen real estate.