Moodle has things it must do internally to keep itself "clean" and "tuned". The cron process is what takes care of these things for it. For your own servers, you'd use crontab -e on linux to add a job that calls the cron process every minute. You can do it less often, but every minute means things are done more timely and the overhead of doing that is very small. Essentially you add a line like this:
* * * * * php path-to-moodle/admin/cli/cron.php
On Windows server, you can do it similarly with Task Scheduler.
On shared hosting, your provider may give you access to cron/scheduling through their control panel, or if you have ssh access, use the linux crontab.
Thanks I appreciated.
