In computer graphics, people speak of screen's resolution as the screen's dimensions: "This screen's resolution is 1280x1024 pixels."
This colloquial usage is wrong, however (just like some people used to speak of bauds when they meant bps). The resolution measures screen's "density" - how big the pixels are, physically.
Screen resolution is usually measured as dots per inch - that is, pixels per inch. For example, this screen in front of me has a screen dimensions of 1280x1024 pixels, and physical size of 361x271 millimeters. This makes the screen resolution 90x96 dpi.
Typical computer screens have resolutions ranging from 75x75 to 100x100 dpi.
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