Courtesy telephone
A courtesy telephone is a telephone located in airport terminals, large train stations, hotel lobbies, and other places where many travellers are expected, which is used to relay messages to a specific person.
It is typically used in connection with a public address system announcement of the style "Jane Doe, please pick up the nearest white courtesy telephone." Courtesy telephones may have a distinctive color, which is traditionally white in US airports, and most have no dialing capabilities but rather are simple ringdown stations to reach an operator or other fixed number. Some double as emergency telephones, having buttons by which a user can distinguish between emergency use and inquiry.