Bing Yahoo PPC
Similar to Google AdWords, Bing Ads uses both the maximum amount an advertiser is willing to pay per click (PPC) on their ad and the advertisement’s click-through rate (CTR) to determine how frequently an advertisement is shown. This system encourages advertisers to write effective ads and to advertise only on searches which are relevant to their advertisement.
Bing Ads allows advertisers to target their ads by restricting their ads to a given set of demographics and by increasing their bids whenever the ad is seen by a user of a certain demographic. As of November 2006, no other PPC advertising system has a similar feature. Similarly, Bing Ads allows advertisers to run their ads on specific days of the week or certain times of day.
Similar to AdWords Editor, Bing Ads provides a desktop tool to manage campaigns offline, called as Bing Ads Editor. Using this editor you can make offline changes to your campaigns and later sync it online.
Bing Ads also provides APIs that can be used to manage advertising campaigns.