Your PC monitor uses the same technology as your television set to produce a picture. The screen consists of many dots or pixels. When the monitor displays text or an image, specific patterns of these pixels light up.

Monitors come in different resolutions. That is, the more pixels your monitor can display, and the closer together they are to each other, the higher the resolution of the monitor. The distance between two pixels is called dot pitch. The lower this number, the better resolution.

The number of pixels your monitor can display is measured both horizontally and vertically. For example, a monitor with a 640 by 480 resolution can display 640 pixels in a row going across the screen, and 480 pixels in a column going down the screen. Or, 640 horizontal pixels, by 480 vertical pixels.

Three factors actually determine the total number of pixels that can be displayed on your monitor: the monitor, the video card that your monitor plugs into, and the software you are running.

The software says what needs to displayed. The video card tells the monitor how to display it. This includes where to display it, and what colors to use. The monitor displays it. The video card and monitor must be matched. Both must have the same specifications.

Finally most monitors can display in a text or graphics mode. Text mode can only display text which is letters, characters, or symbols. Graphics mode can display pictures and text. Text mode is not as pretty as graphics mode. Most PC users prefer graphics mode.