It lets the content of the document to be split into one or more discrete pages. Paged media includes paper, transparencies, pages that are displayed on computer screens, etc.
The CSS2 page model specifies how a document is formatted within a rectangular area (the page box) that has a finite width and height. These features fall into two groups:
-features that define a particular page layout.
-features that control the pagination of a document.
For more in dept: here's an explanation on how to achieve.
But browser support? Not so great i guess...