In CSS terms, a
Even in the “paperless future,” the most commonly encountered paged medium is a printout of some document—a web page, a word-processing document, a spreadsheet, or something else that has been committed to the thin wafers of a dead tree. Authors can do a number of things to make printouts of their documents more pleasing for the user, from affecting page-breaking to creating styles meant specifically for print.
Note that print styles would also be applied to document display in a “print preview” mode. Thus, it’s possible in some circumstances to see print styles on a monitor.
Beyond the obvious physical differences, there are a number of stylistic differences between screen and print design. The most basic involves font choices. Most designers will tell you that sans-serif fonts are best suited for screen design, but serif fonts are more readable in print. Thus, you might set up a print style sheet that uses Times instead of Verdana ...