Urbi et Orbi
Urbi et Orbi ("to the City of Rome and to the World") was a standard opening of proclamations in Imperial Rome.
Now Urbi et Orbi refers to a papal address and Apostolic Blessing that is addressed to the City of Rome and to the entire world from the Apostolic Palace in the Vatican. Usually they are only given at Christmas and Easter, but also the first speech of a new pope is Urbi et Orbi, and sometimes one is given to special gatherings of pilgrims in Rome and during Holy Years
The blessing after the speech is given in Latin, and usually many other languages too. Catholics who listen to the blessing, either because they are present at the Vatican or because they are listening to the radio or television broadcasts, have their sins forgiven because the blessing includes a plenary indulgence.