Hi Joe,
The canvas is really just the volume within which cutpaths are generated within, which can be larger or smaller than your actual workpiece. You can think of it as just the size of your workpiece if that workflow is easiest for you but it doesn't have to be the size of the workpiece as long as you are aware of how it's just a volume of cuts and how that translates to the workpiece based on where you set your machine origin on both the canvas and on your workpiece.
- Charlie