How can I use categories in Contacts?
Categories are labels that help you organize items and find them more easily. You can use categories to organize calendar entries, to do items, contacts, or groups. You can assign category colors, so entries in a category appear in a different color on your calendar.
Add categories to contacts
Procedure
While creating or editing a contact or group, enter categories
into the Category field, separated by commas.
View contacts by Category
Procedure
In Contacts, select By Category in
the navigation pane on the left.