dpi

The abbreviation dpi stands for dots per inch (one inch corresponds to a length of 25.4mm) and describes the dot density that is a measure for the image reproduction quality. It is a measure of screen or printout resolution and the more dots (pixels) an image has and the sharper more accurate the image will be. The specification dpi is used as part of the resolution specification for printer, monitor and digital and video cameras.

With a printer resolution of 300 dpi there are 300 dots per 25.4 mm on a horizontal line.

The standard resolution (image resolution) of the display on the PC monitor is usually 72 dpi or 96 dpi. This value does not say anything about the resolution of the monitor itself. By changing the monitor resolution, the fixed standard image resolution makes the display of text and images appear smaller on high monitor resolutions and larger at low monitor resolutions.

Links

Wikipedia: Dots_per_inch