An error log is a listing of the error messages and warnings that displayed for one reason or another while your visitors were looking through your Internet site. Such a log contains raw information on the way the server has handled requests in different situations. An error message might appear if, for instance, a link leads to a webpage or a file that's not on the hosting server, if the code on a specific page can't be processed, if somebody is trying to access the Internet site or its back office via an IP address that is blocked by an .htaccess rule and so on. The info in the error log offers the IP address of the website visitor, what error message showed up and the basis for the web server to show it, the whole path to the file that induced the error and the precise time of the event. Having this info will enable you to learn if any part of your site has an issue, which you can then resolve. Consequently, your visitors will have a better experience and you will optimize the site for optimum performance.