The most common and typical form of auction. A type of forward auction. A single item is offered for sale. Bidding begins at a low price, rising as bidders accept or call out progressively higher bids. This continues until either the period allowed for the auction of this item is closed or until no higher bids are received. The seller can set a minimum price for sale, called a reserve price. If not bid occurs at or above the reserve, the auction is aborted and the item is not sold.