Safari Books Online is a digital library providing on-demand subscription access to thousands of learning resources.
If you're using C/W Outlook, you can have a Personal Address Book in addition to a Contacts folder. In previous versions of Outlook, it was necessary to have a Personal Address Book if you wanted to create distribution lists. However, now that you can create distribution lists based on Contact items, it's no longer necessary to have a Personal Address Book for that reason.
The main benefit of having a Personal Address Book is that it gives you one place in which to keep information about contacts you frequently use. In a networked situation, you may have to look in several places for various contacts. If you have a Personal Address Book, you can copy contact information from those various places into your Personal Address book to make that information readily available.