From time to time we may wish to perform some maintenance on our site; let's look at three common ways of maintaining our installation:
Cron is the automated execution of tasks by our server. Many Drupal modules perform regular maintenance tasks (for example, pruning log files), by using cron these tasks can be automatically performed at specific intervals.
Setting up cron jobs is quite technical, and depends on your hosting provider too, as not all hosting providers allow cron jobs to run. You should contact your web host for more information on setting up a cron job.
The Drupal handbook online contains ...