Notes: This article is 100% copy from http://www.siteground.com/tutorials/cpanel/cron_jobs.htm

A cron job allows you to run a certain command at times set by the job. For example, you could set a cron job to delete temporary files every week so that your disk space is not being used up by those files.

Check out the Cron Jobs video tutorial:

Cron Jobs Video Tutorial

Cron Jobs Detailed Tutorial

To access the Cron Jobs Menu, click on the corresponding icon located on the main screen of your cPanel interface.

The upper section of the Cron Jobs interface allows you to specify the email address where you would receive an email each time a cron job is ran for your account.

You can enter the desired email address in the text box and click the Update Email button to apply the changes.

The next (lower) section of the Cron Job interface is where you actually set your cron jobs.

There are several common settings that can be used for setting up your cron jobs. In the example above we are showing how to setup a lynx cron job to run twice a day. There is no problem to enter the desired options manually. You can either use the drop-down menus or just type in the text boxes.

Once ready setting up the cron job click the "Add New Cron Job" button and it will be saved and activated for your account.

The bottom part of the Cron Jobs interface will allow you to edit or delete existing cron jobs.