When I'm creating a meeting in Outlook 2007, on the Scheduling screen I
can click the button that reads "Add Others" and choose the "Add from
Address Book" opti9on. A dialog box displays everything in my global
address list, and I can add them as required or optional attendees or as
resources.

I can schedule John Doe as a Required Attendee and I can schedule
Conference Room D as a Resource, but I can also schedule John Doe as a
Resource and Conference Room D as a Required Attendee. What is the
difference between Attendees and Resources? What difference does it make
whether I denote an item as one or the other?