When you click Page Breaks on the View menu, gray lines appear on your drawing. These gray lines indicate overlap: content that falls within them prints twice, once on each of two adjoining printed pages. The gray lines also show you approximately where pages will break when you print.
Many desktop printers support printing only on letter (A4) or legal (A3) size paper. When you print a drawing that is large on the screen on such a printer, the drawing is likely to print across two or more pages.
In Visio, you can see where the pages will break before you print. You can also control the number of pages a drawing prints across and the amount of overlap between the pages.
Note You'll learn more about page breaks in "Control content overlap" later in this course.