GSM networks in Switzerland and Canada

Hi everyone,
I'm interested in buying an unlocked phone while I'm still in Switzerland that I can also use in Canada. My understanding in telecommunications is rather shallow. What I know is that the frequency bands (I prefer to use Sim cards) for the GSM in Switzerland and in Canada are different: http://en.wikipedia.org/wiki/GSM_frequency_bands

I'm not sure what this equates exactly. Has anyone tried using an unlocked phone from Switzerland in Canada and seen it work?

Thank you!
Phone newbie. (I have a Nokia like the ones from the early 2000s still).