The Address Book is a "container" for all of your contacts. This means all of your Contacts folders, e.g., for work, home, social, sales leads, etc., are subsets of the Address Book. When you create a contact in Microsoft Outlook for an individual, the contact information entered for that person is added to the Address Book.
Note: By default, the Outlook Address Book contains all the contacts in your main Outlook Contacts folder. If your organization has a Global Address List (GAL), these contacts are also included. (The GAL is part of the Microsoft Exchange system, more commonly used in business environments and rarely in personal or home e-mail accounts.) If you have created any additional contacts folders, these can also be included.
To add a person to the Address Book, create a contact for that person in Outlook. You do this by using the contact form, an Electronic Business Card, or by saving a person's name, e-mail address, or Electronic Business Card to your Contacts from an open e-mail message. After the contact is saved, the changes are reflected in the Address Book.