user authentication + create user profile

Hi, I need to be able to let the visitors register them selves, a user account should be created in the MySql database, and then the user has access to some "private" pages. QUEST: Any hints on how to 'roll-out' this issue? Is it sufficient to create a user in the database, or should I also make 'm as a user on the operating system? (I'm currently running the site on Linux). Any nice trick, hint, example(code) or fancy idea is very welcome! Yoeri. WISHES: Thant all your dreams( that can be "terrestrallised") may come through! --- Don't torture yourself with "why". Launch the question "How" and you're much closer to the solution than you thought you 'd be ---