What is a Daemon?

Some people use cronjobs for the same Possible use cases. Crontab is fine but it only allows you to run a PHP file every minute or so.

Cronjobs are a bit rude for this, they may spin out of control and don't provide a framework for logging, etc. Creating a daemon would offer more elegance & possibilities. Let's just say: there are very good reasons why a Linux OS isn't composed entirely of Cronjobs :)