A cron job is an automatic task, that executes a particular action - generally executing a script in the website hosting account. The task is planned, which means that it will run on a regular basis - hourly, daily, weekly etc. There are numerous good reasons to use a cron job for your sites. For instance, you can get day-to-day reports how many visitors have signed up on your website, some temporary folder may be emptied automatically each week or a backup copy of the content can be created in a standalone folder in your web hosting account. Employing cron jobs can help you with the administration of your sites since you are able to have numerous things completed automatically and get reports for them, rather than spending precious time and efforts to do them manually.