Log File: a log file is a server file which is automatically created and maintained by user activity. A common example is a web server log, which includes a history of page requests. This data will often include a user's IP address, the date and time the page was requested, URL address used, and more. It can be organized in a number of ways, including one general log file or separate files based on the information being collected. However, log files do not usually collect user-specific information.
The information gathered by a log file is not available to the average Internet user and is limited to a webmaster or administrator. For this reason, a log file is often used as a way to show a site administrator their leading sources of web traffic, as well as what users are searching for to find their website. Unfortunately, log files do not typically give as much data as analytic programs do. If they do, it is generally not as useful, beyond listing a few top statistics. In spite of this, in order to ensure efficient web site administration, marketing departments and web site administrators are typically trained to use log files.