Yahoo is #1 at generating traffic.The level of results when you do a search in Yahoo is as follows. Their listings are called:

1) Inside Yahoo! Matches ~ These are results from any one that has a 'Yahoo Store' that sells that particular product.

2) Sponsor Matches ~ Sponsor Matches are search results that are paid for by businesses or organizations and provided through an alliance with Overture Services (formerly GoTo.com). Only the top 3 positions for a particular keyword are fed to Yahoo!

3) Web Site Matches ~ Are sites that have paid Yahoo $299 annually to be considered for their directory.

4) Web Page Matches ~ Yahoo also gives results outside of their directory (mainly because their directory is so small compared to the whole internet, Yahoo has 1.8 million web pages in their directory database and the Web Page Matches searches 1.8 Billion Web Sites)

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Sponsor Matches are search results that are paid for by businesses or organizations and provided through an alliance with Overture Services (formerly GoTo.com). All Sponsor Matches are individually reviewed by editors for relevance to the specific designated search terms. For example, if you search for "Digital Camera," you'll find Sponsor Matches for web sites that provide information on digital cameras and/or sell digital cameras. In addition to Sponsor Matches, you'll find categories and web sites related to the topic of "digital cameras." To make it easy to distinguish Sponsor Matches, Yahoo! search results display Sponsor Matches apart from Inside Yahoo!, Yahoo! Categories, and Web Sites.

Through Yahoo! Express, we can ensure that sites suggested by merchants such as yourself are viewed and evaluated in a timely manner by Yahoo!'s editorial staff. Your payment and participation in Yahoo! Express guarantees that within seven business days a member of Yahoo!'s editorial staff will look at your site and consider it for inclusion in the Yahoo! directory. Please keep in mind that payment does not automatically guarantee inclusion in the directory, site placement, or site commentary. Click here for details.

Yahoo also gives results outside of their own directory, mainly because their directory is so small compared to the entire internet, Yahoo's Directory has only 1.8 million web pages in their database and the Web Page Matches searches 1.8 Billion Web Sites utilizing Google's data base.