If the process of selecting a new Pope sounds like something from another century, that's because it is.
More than 100 cardinals take a vow secrecy inside the Sistine Chapel and with the exception of a few workers at the Vatican no one else is allowed in.
The doors are then locked to ensure secrecy and prevent influence from the outside world. Internet, radio and television communications are also removed.
Until a new Pope is chosen, the cardinals live in a special residence in the grounds of the Vatican.
The cardinals are handed voting papers to write the name of the person on they have selected. They take it to the altar approach where they leave it on a plate, pray and then place it in an urn.
The names are counted and if a name has received two-thirds of the votes, the pope has been elected.
If the first ballot does not produce a result, the process is repeated for three days, after which there is a day's rest for prayer, reflection and informal discussions.
The voting then begins again for a series of seven more ballots and then another break.
The process is repeated twice more and if there is still a stalemate, the chamberlain will declare a result can come from an absolute majority or by a vote on the two names that received the largest number of votes in the last ballot.
After voting, the ballots are burned with chemicals to make the smoke either white or black. White smoke from the chimney of the Sistine Chapel signals the election of the pope and black smoke means the cardinals have not come to a decision.
In a more recent addition, bells are also rung when a new pope is selected.