What is a Cron Job

A Cron Job is a task that should be executed repetitively at regular intervals. It is an action that only your server is capable of scheduling.

Example: the website weekly-backup that most hosting companies offers to their clients, is a classic example of a Cron Job. The server has scheduled the backup operation on, for example, every Saturday night at 00:00.

Crons consist of a server-command that is executed at regular intervals: every day, every month, every Saturday, at midnight, every 10 minutes, every hour etc.. In order to set up such repetitively actions, your server requires a 'Cron Utility' to be installed. One of the most popular Cron Utility for Linux Severs is crontab. Imagine that this utility is like a software installed on your personal computer, it's a 'daemon'/'service' running on your server instead.

If your server has a Control Panel, then you should check if a feature called 'Cron Jobs' exists. You should ask your hosting company if your server supports any Cron utility to schedule Jobs.
Once you know whether your server supports such functions, you just need to find the command that the server should execute at regular intervals.

VikBooking comes with 3 default Cron Jobs Schedulers: Email Reminder, SMS Reminder, Invoices Generator. Once you will have configured any of those crons, the system will let you download a .php file that your server will have to execute. The Command for the Cron Job will make your server execute this .php file at the desired intervals, to accomplish the actions you configured.