Hey there Gert,

You can resize the canvas by going to File > Document Setup. In the top right hand corner of the dialogue window there's a button that says Edit Artboard. It will then highlight the artboard selected. You can then press Enter (Return) and it will open up the Artboard Options where you can change the size, orientation, etc.

You can also select the artboard using the "artboard tool" located in the toolbar which looks like a square with little tick marks at the corners. In either case the artboard options will also show up in the top bar if you want to quick adjust items without having to go into the dialogue window.

I'm using CS5 on a mac but I'm assuming the process is at least somewhat similar.

Hope this helps!

-ben

While I do not at all like the 227 inch restriction being in the large format print business the terms do often get confused. Sadly the ability to make the canvas itself larger is not a new feature in CS6.   80% of our work is done in Illy and while we can work at scale for what we do why should we have to? When designing for a 648" trailer (yes 54 foot), we need to print and/or cut the design at full size. So we always have to increase the files in our print system by 400% or whatever which is an unnecessary step.

As far as the terms, the main background is indeed called the canvas. It is not possible to change the size of the canvas. Period, not happening in Illustrator although most other vector programs do allow this. Artboards sit on top of the canvas and essentially act as containers (and print clipping masks) for artwork. Artwork can also be outside of the artboards, if printed anything outside of the artboards will not print. You can also have multiple artboards on the same canvas. Adobe has a decent explanation of the canvas and artboards here http://helpx.adobe.com/illustrator/using/artboard-overview.html

Yes! Thanks for asking this question and for Ben's answer - super helpful.