An access log is a text file containing an extensive list of all of the files accessed by your website visitors. All of the files that were requested in one way or another shall be included, so if you have a PHP script application and a visitor opens only the home page, for example, you might find many files in the log. The reason is that there are components on the home page that are embedded - parts of other Internet pages, graphics, and so forth. All these files shall be listed in the access log, so you're able to get a complete picture of the way your site performs. The information is in plain text format, so the logs are often described as "raw data" too. An access log contains the name of every requested file, the path to it, the date it was accessed, in addition to the user’s IP address, Internet browser and OS. More info, such as the referrer website, is oftentimes supplied as well. A log file may be processed by various desktop programs for statistical purposes as an addition to the web stats provided by your hosting server.