Absolute Auction Better known as a “straight auction,” an absolute auction has just one item up for sale. The seller sets an opening price and does not use a reserve price. The high bid wins the item, even if only one bid is received, and it is no higher than the opening price. Many online auction sellers use this format.

Antique In some categories of goods, an item at least fifty years old is considered “antique.” Under U.S. Customs regulations, an item must be at least 100 years old to qualify as “antique.”

Appraisal An expert's opinion of an item's value. An appraisal may be given informally (“Old chairs like this one have been selling for around $200 lately.”), or it may be stated in writing.

As Is Property “as is” is sold without any warranties or guarantees regarding its condition or suitability for a particular use. When you buy something “as is” in an online auction, it is up to you to examine and judge whether the property will meet your needs or desires. This may mean trusting the seller's descriptions, posted photographs, and reputation on the auction site. Other terms with similar meaning: “As is, where is” and “In its present condition.”

Auction Value An auction item's current bid. The value changes as the bidding goes higher.

Auction with Reserve See Reserve Auction.

Bid Cancellation The process of removing a potential buyer's bid from an item. A seller may cancel a bid only under special circumstances.

Bid History A list showing the user IDs of bidders, how much they have bid, and when they placed their bid in a current auction.

Bid Retraction The act of removing a bid from an item in an online auction. A bidder may retract a bid only under special circumstances.

Dutch Auction An auction in which the seller has listed multiple quantities of an identical item. Several buyers can bid and win, or one bidder can try to buy up many or all of the quantities. This practice is known as “buying up lots.” In a Dutch auction, all winning bidders pay the same price: the lowest successful bid. This is the opposite of what happens in a Yankee auction. There, each winning bidder pays his exact high bid.

Federal Reserve System The Fed is the central bank of the United States. It incorporates twelve Federal Reserve branch banks, all national banks and state-chartered commercial banks, and some trust companies. In general, the Fed tries to keep the U.S. economy on an even keel by raising and lowering short-term interest rates and the money supply.

Federal Trade Commission The Federal Trade Commission tries to ensure that America's markets are “vigorous, efficient and free of restrictions.” The FTC also enforces consumer protection laws and guards against Internet scams, among its other duties.

Insertion Fee This is eBay's term for an auction listing fee. Other online auction sites often use “listing fee” when charging an item to be listed.

Live Auction An auction that takes place in real time, either in an auction venue with an auctioneer and buyers or online.

Lot A single item or a group of items being auctioned.

MIB This label on an auction item means “Mint in Box” condition. That means its original package has never been opened.

MOC This label on an auction item means “Mint on Card” condition. This often refers to a toy or other item that is still packaged on its original card and usually inside protective plastic

NR (No Reserve) This description means that an auction item does not have a reserve price that has to be met before it can be won with a bid.

Provenance This term refers to an item's line of ownership. For example, an unusual or interesting provenance can add to an item's value, if ownership by a celebrity, a notorious person, or an important historical figure can be demonstrated.

Proxy Bidding At an online auction site, this is the process of entering the maximum price you are willing to pay, and then letting a computer bid on your behalf. The proxy bidding agent will raise your bid just enough to keep you ahead, unless the price rises above your preset maximum.

Registration The process of opening a buyer or seller account on an online auction site. Typically, you have to provide personal information including name, address, telephone number, and e-mail address, as well as credit card information. Some online auction sites may require other information, as well.

Relisting This is to put an item up for bid again, after its first auction didn't attract any bids, or its reserve price was not met.

Reserve Auction In a reserve auction, the seller posts an opening price but also sets a reserve price, which is the lowest he will accept. The reserve price is not revealed to bidders. If bidding exceeds the reserve price, the online auction site will post a message stating that the reserve price has been met. The seller is then obligated to sell the item to the highest bidder.

Reserve Bidder The bidder who places the second-highest bid. If the high bidder backs out or is disqualified, the item can go to the reserve bidder, if she still wants to buy it.

Reserve Price The price established by an owner for a lot to be sold at auction. The owner may legally refuse to sell the item for a price below this amount. The reserve price does not have to be disclosed before the attempted auction of the item.

Retaliatory Feedback When a buyer posts negative feedback for a seller, because of shoddy merchandise or some other dispute, the seller sometimes may retaliate by posting negative feedback for the buyer.

S&H This is auction site shorthand for “shipping and handling.”

Shilling (or Shill Bidding) This is a fraudulent practice in which the seller, using another auction account, bids on his merchandise to push up its price or has a willing associate do the bidding.

Sniping The process of placing bids in the very last minutes or seconds of an auction, when there is almost no time for another bidder to respond. Bid sniping software sometimes is used to place a bid at the very last moment.

Terms of Service Online auction sites usually have these sets of rules and guidelines that buyers and sellers must observe. Otherwise, they may lose their ability to buy or sell on the site.

Valuation An expert's written or spoken opinion of an item's worth.

Value In online auctions, an item's “value” is measured by how much money the highest bidder is willing to pay for it. Before auctioning it, a seller may have a good sense of its value but will not know exactly how much until the auction ends.

Vintage This term, popular in auctions, applies to something that is old, relatively speaking, within its group or category. It may not necessarily be very old in terms of years. For example, a “vintage” record might be fifty years old, while a “vintage” Beanie Baby might be ten years old.

Viral Marketing A marketing technique that encourages people to pass information such as a Web address to their friends and others, via e-mail. If the recipients also pass the information to their contacts, it can keep spreading from person to person, like a virus.