Rules for showing hands at Showdown

I can never get this straight-- who has to show their hand first at SD in a live game? Is it the caller or the bettor/raiser? If it's checked down, who shows first?

In the hand whoever made the last call does not have to show their hand unless they want to win the pot, if its a loser then they can muck. The mucked hand can be requested to be viewed but its poor ettiquitte.

The person who calls shows LAST. "I call" = I am paying to see what you have.

When a hand is checked down the last person to check is in essence calling a zero bet so the last checker would again be the LAST one to show (or muck).

On the final betting round, the person that initiated the action is required to show first. In most cardrooms if their is no action on the final betting round then the first person to the left of the dealer is required to show. In some cardrooms, like the B&M I typically play at, if there is no action on the final betting round then the person that initiated the last action is still required to show first, even if it was on a previous betting round.