eBay can be used by individuals, companies and governments to purchase and sell almost any legal, non-controversial item. eBay's auctions use a Vickrey auction (sealed-bid) proxy bid system. Buyers and sellers may rate and review each other after each transaction, resulting in a reputation system. The eBay service is accessible via websites and mobile apps. Software developers can create applications that integrate with eBay through the eBay API. Merchants can also earn commissions from affiliat