I want to know how to do programming of executing automated task every day in PHP.

For ex. every day there might be some visitors whose Registration gets expired so every day this script should run automatically & execute the code wihtout any human intervention.

I know there is something like Cron Jobs but dont have much idea of the same w.r.t executing Cron jobs on Online Web Servers.

I am working in PHP & mysql. Please suggest.

Thanks in advance.

Ani