How Do You Have Your House Paid For When You Die?

Does anybody know? I know there's a way to do it & I'm assuming it involves purchasing some kind of special insurance, but I don't know if I should be contacting my mortgage lender, a realtor, a life insurance agent or who? Plus, I don't even know what the process itself is called. What do I ask for when I finally do contact whoever it is I'm supposed to contact? Does this sound familiar to anyone? Thanks.