An access log is a text file that contains a full list of all the files accessed by your site visitors. All of the files which were requested in one way or another shall be included, so if you have a PHP script program and a visitor opens just the home page, for example, you might find numerous files inside the log. It is because there are elements on the home page which are embedded - parts of other pages, pics, etc. All these files will be listed in the access log, so that you can get a complete picture of the way your site works. The info is in plain text format, so the logs are frequently termed "raw data" as well. An access log provides the name of every requested file, the path to it, the date it was accessed, plus the user’s IP address, Internet browser and OS. More information, such as the referrer website, is sometimes provided too. A log file could be processed by various desktop apps for statistical purposes as an addition to the web statistics created by your website hosting server.