The online auction business model is one in which participants bid for products and services over the internet.
When one thinks of online auctions they typically think of eBay, the largest online auction site. Like most auction companies, eBay does not actually sell goods that it owns itself. It merely facilitates the process of listing and displaying goods, bidding on items, and paying for them. It acts as a marketplace for individuals and businesses that use the site to auction off goods and services.
Several types of online auctions are possible. In an English auction the initial price starts low and is bid up by successive bidders. In a Dutch auction, multiple identical items are offered in one auction, with all winning bidders paying the same price -- the highest price at which all items will be sold. (Treasury bills, for example, are auctioned this way). Almost all online auctions use the English auction.
eBay Inc. manages an online auction and shopping website, where people from all around the world buy and sell goods and services.
Millions of collectibles, appliances, computers, furniture, equipment, vehicles, and other miscellaneous items are listed, bought, and sold daily. Some items are rare and valuable, while many others are dusty gizmos that would have been discarded if not for the thousands of eager bidders worldwide, proving that if one has a big enough market, one will find someone willing to buy anything.
It is fair to say that eBay has revolutionized the collectibles market by bringing together buyers and sellers internationally in a huge, never-ending yard sale and auction. Large international companies, such as IBM, sell their newest products and offer services on eBay using competitive auctions and fixed-priced storefronts. Regional searches of the database make shipping slightly more rapid or cheaper. Software developers can create applications that integrate with eBay through the eBay API by joining the eBay Developers Program. As of June 2005, there were over 15,000 members in the eBay Developers Program, comprising a broad range of companies creating software applications to support eBay buyers and sellers as well as eBay Affiliates.
In June 2004, eBay prohibited the sale and auction of both alcohol and tobacco products on the British site ebay.co.uk. Some exceptions to this rule are made for rare aged liquors, where a bottle may sell for many times higher than its actual value in alcohol.
There has also been controversy regarding items put up for bid that violate ethical standards. In late 1999 a man offered one of his kidneys for auction on eBay, attempting to profit from the potentially lucrative (and, in the United States, illegal) market for transplantable human organs. On other occasions, people and even entire towns have been listed, often as a joke. In general, the company removes auctions that violate its terms of service agreement within a short time after hearing of the auction from an outsider; the company's policy is to not pre-approve transactions. eBay is also an easy place for unscrupulous sellers to market counterfeit merchandise, which can be difficult for novice buyers to distinguish without careful study of the auction description.