If your phone has a Calling ID display screen, you will be able to see the number of the person calling you before you answer (or don't answer) your phone. Note if the person calling blocks their caller ID, you won't be able to see it
You can set up your phone to automatically reject calls from people who block their caller ID
When making an outbound call, your phone number will be presented to the person on the other end, provided they have Calling ID enabled on their side (better get them to sign up for a engin service!)
If you don't want the person you are calling to see your number, you can block Caller ID either all the time, or on a call by call basis
While you are on a call, the call waiting beep will advise you of another call waiting to be answered
Enables you to conference in a third person to a call
You can set your phone up to forward incoming calls to another number
If you need some peace and quiet, you can send all incoming calls directly to voicemail
When you are unable to answer a call, engin voicemail will take a message for you. You can then listen to the voicemail over the phone
Receive an email alert when a new voicemail arrives. The email will also contain a sound file of the voicemail that you can listen to right on your computer