I've started browsing through the book and this isn't clear (maybe it gets answered there somewhere--if so, sorry for the bother).

The book, so far anyway, keeps talking about the Drupal installation and "Your site" like there's a one-to-one relationship. This raised the question for me: If I want to host multiple sites (www.mysite.com and www.mycustomerssite.com, etc.) on my server, do I need multiple installations of Drupal?

Thanks.