BOSS API is an updated service that provides RESTful access to Web, Image, News, and Spelling with a simple pricing scheme based on usage. The service also provides qualifying developers access to Yahoo Search Advertising.
Web search and Image search results are provided by Microsoft Coporation through the Yahoo and Microsoft Search Alliance.
BOSS API is the next step in the BOSS product evolution. Yahoo has retained the best features from the original BOSS release and added some new features to enhance the build your own search service experience.