What does the outside border represent

When designing in Illustrator on a blank template, what does the outside border represent. Should I keep within that border?

Think of it as the edge of the canvas. Anything that falls off the edge of it cannot be printed...You're printing area is going to be determined by your page setup. The size of your document can be changed under document setup.

(Created by Tyberius Prime on 12-26-2004 23:16)