From its very beginning, the prospective of extracting precious knowledge from the web has been relatively marked. Web mining i.e. application of data mining techniques to mine knowledge from web content, structure & usage is the collection of technologies to accomplish this potential. Interest in web mining has grown rapidly in the short period of time. Today there are several billions of HTML documents, images and other files available on WWW via internet and the number is still getting bigger. But taking into consideration the exciting diversity of the web, retrieving interesting content has become a very difficult task.