hey /trv/

I'm an Amerifag but I live in Las Vegas which is a huge tourist town so I get to interact with lots people from different countries. We get our fair share of brits and aussies and such and one thing that I've never quite understood is the meaning of the word "cheers". Here in the US we only say it when we're giving a toast of some kind, but I've had brits and other miscellaneous commonwealth people say it to me and I've never had any idea what they mean by it or how I should respond.