An access log contains a record of all the files which have been requested by the visitors while exploring your site. The list is comprehensive, so when you have a webpage with 2 embedded images, for instance, all of the three files shall be in the log, not just the page. An access log usually contains the date, the Operating System, the Internet browser and the IP address for every file in human-readable form, so you can get an idea about the most popular files on your Internet site. The log, which is also typically referred to as "raw data", is an addition to the web data you commonly get with a hosting account, not a replacement. A good example why you might need this type of a log is if you intend to use some software on your computer system to prepare a report about the website’s overall performance, but you don't want to use the conventional graphs and tables which come with the server-generated site statistics.