An error log is a list of the error messages and warnings which showed up for one reason or another while your visitors were surfing around your Internet site. This sort of a log includes raw information about the way the hosting server has addressed requests in different situations. An error message may 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 particular page cannot be processed, if somebody is trying to access the site or its back office through an IP address which is blocked by an .htaccess rule etc. The info inside the error log offers the IP address of the website visitor, what error message appeared and the reason for the web server to show it, the whole path to the file that triggered the error and the precise time of the event. Having this info will permit you to find out if any part of your Internet site has an issue, which you could then fix. For that reason, your visitors will have a better experience and you'll optimize the site for optimum performance.