The address book was made because there's a need for accesible contact data, data that's needed via a web browser.
It manages contacts, and integrates nicely with the RFC822Message (mail- / newsmessage) facility.
Title A descriptive title, used in navigation and identification
The group that is by default displayed when the AddressBook is entered
Groups are used for easily displaying contacts, and selecting to whom to send email, when used in the GUM.
When entering the addressbook you will be presented with a listing of contacts from the default contact group.
To display another group, simply select it from the selection on the right hand side and click show.
Contacts can also be listed alphabetically, clicking on any of the letters will list up all contacts which have a surname, firstname or nickname which starts with the given letter.
If the GUM (Messenger) is installed, you can also easily click on any of the listed email addresses to start composing a new message.
The groups button will bring you to the group management view, where you will be able to add new groups, and delete existing groups.