In the Catholic Church to choose a new pope, it is mandatory for every cardinal under the age of 80 to travel to Rome to take part in the secret conclave election process which begins with a mass celebrated in St. Peter’s Basilica followed by a procession to the Sistine Chapel.
Before the cardinals arrive, the Sistine Chapel goes through a comprehensive check or unauthorized microphones, recording or other communication devices. The phones of the cardinals are also blocked to prevent them from communicating with anyone about the election.
At the outset, the 115 cardinals participating in the election process this year took an oath of secrecy. After that the first voting process began. Each cardinal could cast one vote, except for himself. A candidate for the papacy must receive two-third of the total votes. This voting process continues with four voting sessions – two in the morning and two in the afternoon – for five consecutive days, or until the pope is chosen.
At the end of each voting session the smoke from the burned ballots billowing out of the chimney on the roof of the Sistine Chapel reveals to the public the outcome of that voting session: black smoke to mean no consensus reached, and white smoke to announce the successful choice of a new Pope.