Specify other information that you would like your Address Book Entries to include. The headings that you choose will be shown in the Address Book Entries' Notes Pane and information can be entered in the Address Book Entry's Notes tab.
Enter titles for the User-defined field in the Field sections. For example,
you may wish to write down the names of the person's children, or their
favorite type of restaurant. Use the User-defined fields to record any
other important information that is not already included in the General,
Business and Personal tabs of the Address Book Entry dialog.
See also:
Setting your Address Book's columns