First find the person's name & address. His communications data then appear in the left hand window above. To dial the number just click the Phone button. During your conversation you can update the person's diary, dossier, profile, figures, the subjects and issues in which you share an interest, his account with you, details of your mutual friends and acquaintances - in fact any of his data. A note that you have made the call to him is placed in his diary automatically. It is also recorded in his profile as the last event to have taken place between you. To terminate the call just hang up your phone.
The above box is simply an image. When implemented as an applet, the operation of each button is displayed on the browser's status bar when the mouse pointer is over the button concerned.