eBay is the world's first, biggest and person-to-person online trading community. It's a place to find the stuff you want, to sell the stuff you have and to make a few friends while you're at it.
Buying items on eBay is a snap. After registering, a person can search for an item that he or she is looking for, view pictures of the item and make a bid. Bidding may be open for two or three days. After that time, the person receiving the bids chooses the highest bidder and notifies the buyer.
Similarly, a person can list an item to sell. Selling an item requires that the person give a description of the item, a URL for any photos available, and placing the item in the correct category, such as antiques, coins, toys. After filling out the "sell your item" form, the seller is ready to sit back and watch the auction progress.
Ebay offers a variety of built-in safeguards for people buying and selling items. Insurance, escrow services, and arbitration are available to help assure people of making a fair exchange.
Excerpts (parts taken) from the eBay site.