Variety show formats?

This is a question for the older folks on Yahoo (no offense). I've been thinking about starting a TV show here at my college and I was wanting to do a variety style show. My mom says that I'd be well-suited to the Carol Burnett/Dean Martin style variety show, but I don't know what those shows were like; I've seen clips, not full episodes, so I can't figure out how the show was structured. So for those who were around then, what was a typical episode of these shows like? What would usually happen?