
Web applications are increasing at an enormous speed and its users are increasing at exponential speed. The evolutionary changes in technology have made it possible to capture the users’ essence and interactions with web applications through web server log file. This is a study on web log mining application Web log files store data related to the use of a web site. Analyzing these data in details is therefore this more complicated task for improving the user browsing experience. Preprocessing being preliminary and essential step to data cleaning, data filtering, path completion, user identification, session identification. In this paper deals with a introductory idea about the web log mining and data preprocessing in the web data.