An access log is a text file containing an extensive report on all of the files accessed by your site visitors. All the files which were requested in one way or another shall be included, so when you have a PHP script application and a visitor opens just the home page, for instance, you might find many files inside the log. The reason is that there are elements on the home page that are embedded - parts of other webpages, pics, and so on. All these files shall be listed within the access log, allowing you to get a detailed picture of the way your Internet site functions. The information is in plain text format, so the logs are often termed "raw data" as well. An access log provides the name of each and every requested file, the path to it, the date it was accessed, and also the user’s IP address, browser and OS. Additional information, including the referrer site, is sometimes provided as well. A log file can be processed by various desktop apps for statistical purposes as an addition to the web statistics generated by your server.