The
service allows you to check the voice mail not being by the phone or computer where the mail
comes. All one has to do is dial a special number (usually given by the
communication provider) and listen to voice mails.
In telecommunications the automatic call-back is a computer telephone function which allows the user by the engaged addressee’s line or in the other case of the subscriber’s inaccessibility indicating the system to save the number of the called subscriber and make the call when the line will be available or when the called number is not engaged.