The growing usage of the web has unfolded the Web mining technology to a great extent. Web mining helps in extraction of useful knowledge from web data. (i.e. a range of web pages, hyperlinks among various pages, web sites usage logs and so on. This paper has threefold aspect. Firstly, it defines how web mining research area focuses on mining research and retrieval research (i.e. retrieval of data, information on web, data and text mining). Secondly, it categorizes the Web mining as content mining (i.e. retrieval of information from texts, images and other contents), structure mining (i.e. finding of facts from association of web pages) and usage mining (i.e. mining of information about usage of web sites). Web content mining mainly focuses on the structure of inner-document whereas web structure mining aim is to discover the linkage assembly of the hyperlinks at the inter-document level. Web usage mining includes three ¬¬major phases i.e. preprocessing, pattern discovery and pattern analysis. Thirdly, it focuses on natural language processing as a backbone for web content mining that helps in handling of unstructured data over the web by offering various techniques. This paper concluded the web mining as trending research area for various research communities such as Databases, Artificial intelligence, Information retrieval and E-commerce.