cron is a Linux utility that schedules a command or script on your server to run automatically at a specified time and date. A cron job is the scheduled task itself. Cron jobs can be very useful to automate repetitive tasks.
For example, you can set a cron job to delete temporary files every week to conserve your disk space. Some programs, such as Drupal, may even require you to set up a cron job to perform certain functions. Scripts executed as a cron job are typically used to modify files or databases. However, they can perform other tasks that do not modify data on the server, like sending out email notifications.
