The Address Book in Outlook is actually a collection of address books of different types and formats. These address book types are covered in FAQ 3.3. Regardless of the exact address book type, all address books enable you to save contact information for your business acquaintances, friends, colleagues and so on. For example, you can store information such as the following and much more:
Display name (such as a nickname)
When you are composing an e-mail and enter a name in the To, Cc (carbon copy), or Bcc (blind carbon copy) fields, Outlook automatically searches the Address Book for the entered name and inserts the e-mail address ...