An access log is a text file that contains a complete report on all of the files accessed by your site visitors. All the files which were requested in one way or another will be included, so if you have a PHP script application and a website visitor opens just the home page, for instance, you may find a lot of files in the log. The reason is that there are components on the home page that are embedded - parts of other Internet pages, pics, and so on. All of these files will be listed in the access log, so that you can get a detailed picture of the way your site performs. The information is in plain text format, so the logs are sometimes described as "raw data" too. An access log shows the name of each requested file, the path to it, the date it was accessed, plus the user’s IP address, browser and OS. More info, like the referrer site, is oftentimes provided as well. A log file may be processed by various desktop programs for statistical purposes as an addition to the web stats generated by your server.