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Several types exist. (1) An English auction is the most common style. Bidding begins at the seller's minimum acceptable price. Every new bid increases the price. Each bid is a fixed increment. Every bidder knows the existing bid price. The winner is the highest bid price bid not one else will exceed. This type of auction is often time-bound. (2) A Dutch auction is a reverse auction. Bidding begins at an unacceptable bid price and lowered by set increments until one buyer accepts the bid price. Perishable items, like flowers and vegetables. are typically auctioned this way. (3) A Japanese auction requires every buyer present to bid at every stage during the auction. Bidding begins with a low bid price, increasing in regular increments. (4) A Yankee auction allows multiple units of an item to be available for bidding. Each bidder specifies the quantity being bid as well as the price. In general, it is a common auction. One seller offers one or more items for bidding. Several buyers compete, offering a price the seller will accept. The seller usually has the option to accept any bid or reject all. It continues until no one buys or one buyer wins out.