That is a bid on one lot OR another. If you are not the high bidder on the first lot, the bid will be applied to the second lot. In case of tie bids, the earliest postmarked bid wins the lot. Ties are rare but they do happen. Frequently lots are won by adding a small increase to your bid.
Lots usually have a reserve, that is a minimum bid set by the owner of the item.
While reserves are not published, they do exist. Lots containing ten or more stamps are normally not returnable so consider your bids carefully on these items. You may call us for guidance and questions on bids. We are happy to help you. We were beginners too, at one time.