Pot Luck Protocol

I recently went to a potluck party and chose to bring a dessert for the get together. It got me thinking about whether there was a protocol on what to bring to pot lucks. I've found that the food usually consists of everything from made-from-scratch items to picked-up-from-the-drive-thru dishes. And I understand that some people are cooks and some just aren't.

So is there a protocol when it comes to what to bring to a potluck?

I think the bottom-line is that as long as it fits the requirements (party theme, casual get together vs. a nicer holiday party, budget restraints) then all dishes are welcome. What's even better is if you can supply a throw away container so that there's no need to keep tabs on your serving platter!