Private Auction is for those who backorder names. If multiple people backordered the same name, they will go in Private Auction. Reverse Auction are names that no one wants... but enom want to take the chance and grab them as they are dropped, and let people bid as it go down in price from $120 to $0. As for Public auction, it includes names that are from reverse auctions and as well as those pre-release ones. Hope it helps...