How do templates work?

[leviw]

Hi all,

I'm not looking for any hands-on technical assistance, more for a general description of how templates work.

For example, when a php page loads and comes to a $demotemplate marker, how does it know where the appropriate text is?

After looking around I am a bit puzzled, I'm sure I'm missing something obvios but if someone could run it by me in simple terms I'd really appreciate any pointers.

Since php.net doesnt really use such things I'm assuming even the term itself is based more out of a user need than any actual php code.

Does $demotemplate link to a permanant variable, or a database table somewhere?

More importantly, how would one go about setting up a NEW template outside of vbulletin? I can go into forum/admin and make one, and link to it, but where is it stored?

Thanks for any tips!