Call waiting with “Caller ID” uses a special signal in
order to warn you about an incoming call, during another call there are shown the
name and number of the calling subscriber on the display. The function also
allows switching between two calls.
The handling of incoming and outgoing phone calls. The incoming calls
are those which you receive from your clients. The outgoing ones – calls to
your clients, suppliers and other contacts. The very service is provided by
special companies, most often by telemarketing call service centres.