bait-and-switch tactic: A variation on the old sales technique of pretending to sell what you’re not really selling, and then tricking the buyer into shelling out for something pricier.

bid increment: The amount of money by which a bid is raised.

blog: An online journal.

broadband: A high-speed Internet connection. DSL and cable are two types.

by proxy: The automatic-bid feature in eBay. It stands in for you so that your eBay bid rises incrementally in response to other bidders’ bids.