An access log is a text file containing an extensive report on all the files accessed by your site visitors. All of the files which were requested in one way or another will be included, so if you have a PHP script app and a visitor opens only the home page, for example, you might find a lot of files inside the log. The reason is that there are elements on the home page that are embedded - parts of other Internet pages, pics, and so forth. All these files will be listed within 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 sometimes referred to as "raw data" as well. An access log shows the name of each and every requested file, the path to it, the date it was accessed, along with the user’s IP address, web browser and Operating System. More information, such as the referrer Internet site, is sometimes included too. A log file may be processed by various desktop programs for statistical purposes as an addition to the web statistics created by your server.