Automated Web Scheduling?

[#1]

PHP / CGI guys,
on Planet PlusNet, is there a way of scheduling jobs/program runs, using something like a 'web scheduler'?
Web schedulers work by creating a virtual client on the server and then 'load' a web page against a predefined schedule. They are used for running jobs like file collection/clean up, mailouts, and automated database optimisation.
Cheers,
Thunderclap

[#2]

Hi Thunderclap,
Sounds like the sort of things you want doing could be done by the Cron daemon, which you should have access to... please post back if this is something you're not familiar with and I'll grab some documentation for you.
Cheers,
Matt

[#3]

Matt,
the Cron(ograph) sounds interesting. I would be grateful for any documentation links as PHP/CGI is a bit of mystery to me - I do non-unix related development. Note that I didn't say windows there.
I would want to run a simple application that functions as a 'watchdog' for another website every hour - If the watched site does not respond with an http 200 response, then the application issues an email.
Thanks,
Thunderclap