The service often seen at different sites works in such a way that you
need to enter your telephone number in a special window and after some seconds
you and the company representative will receive a call, which will allow you
communicating.
A message which is played to the called party before answering the call, in the most cases the message tells who is calling, the name or telephone number helping you to decide how to answer to the call and sometimes whether to answer it at all.