Abstract: Web mining merges two areas of research: the World Wide Web and data mining. Web mining is applying data mining methods to estimate patterns from the data present on the web. This helps in improving web based services. It also has various commercial uses in the areas of artificial intelligence, business support services, personalization of web services and so on .Effective user behavior patterns can be found by applying mining techniques like clustering and association rules to web log data. This paper provides the overall perspective of web mining. It mainly focuses on the application of various data mining techniques to web data to obtain patterns of web usage.