An auction is the process of buying and selling things by offering them up for bid, taking bids, and then selling the item to the highest bidder. Auctioning can be traced as far back as 500 B.C.[1] In economic theory, an auction is a method for determining the value of a commodity that has an undetermined or variable price. Auctions can be with reserve or minimum, or without minimums, or absolute or no reserve. In reserve auctions, there is a minimum bid or reserve price; if the bidding does not reach the minimum, there is no sale (but the person who puts the item up for auction may still owe a fee to the auctioneer or auction company). In absolute or no reserve auctions, the sale is guaranteed, with only the price left to be determined. In the context of auctions, a bid is an offered price.