- cron - is a daemon used to run scheduled tasks such as system backups, updates and many more. It is suitable for running scheduled tasks on machines that will run continuously 24/7 such as servers
- anacron - is used to run commands periodically with a frequency defined in days. It works a little different from cron; assumes that a machine will not be powered on all the time. if an anacron job was missed because it was during power-off, it would be executed during boot