Restricting Users On Intranet Site

I'm an IT for my company and I've been handed the job of building the local intranet site. I've built one in standard html, and is looking ok, but my boss wants me to have some of the pages restricted from some users. Can somebody explain in detail how can I set this up so that some users (ie: managers) can access all parts of the intranet site, and standard users can only access certain parts of the site?

I have a ton of experience building sites in HTML and PHP, but do not know much about setting this type of authentication or whatever on a Windows server 2003.

Any help would be much appreciated :thumbup1:

Thanks,

Jeff Bolin

Here you go : http://support.microsoft.com/kb/326214/en-us

Much obliged.

Jeff