There are quite a few differences in individual search engines, on the basis of algorithm. Yahoo likes more links, counts all backlinks while determining a page’s importance.

It gives importance to on-site optimization. Whereas on the other side, Google considers the quality and content of the links while determining a web page’s importance. MSN considers the keywords in the content of the webpage. So, Google looks into the Quality aspects of the links whereas Yahoo and MSN symphathises on the Quantity of links rather than the Quality aspect. So, it's tough to get higher rankings in Google but not that hard in Yahoo and MSN.

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