The conclave to elect the next pope will begin on May 7, the Vatican has announced. Following the death of Pope Francis, some 135 cardinal electors will take part and vote for the new pontiff. 

Cardinals from all over the world will travel to Rome and will stay until a new pope is chosen. Of the 252 current ones, there are 153 cardinal electors - those under the age of 80 - including 53 from Europe and 18 from Africa. The rituals of the event, held in the Sistine Chapel in Vatican City, are elaborate and date back several centuries.

When Pope Francis died on Easter Monday, the Catholic Church entered a period known as "sede vacante", meaning "empty seat". 

His ring and seal, used to disptach papal documents, were broken to prevent anyone ekse from using them.

Cardinal Kevin Farrell - the Camerlengo (chamberlain), who announced Francis's death - became the interim chief of the Church.

Once the conclave begins, the cardinals will not emerge from the Vatican until a new pope has been chosen. While holding voting sessions, the cardinals will sleep in the Casa Santa Marta, a guesthouse inside the Vatican's grounds.

While the concave is ongoing, cardinals are unable to communicate with the outside world - phones, internet access and newspapers are not allowed.

The word "conclave" comes from the Latin, meaning "with key" - a reference to the isolation in which the cardinals are kept. 

On the first day, one ballot is held. After this, the cardinals hold two daily votes until one candidate has a majority of two-thirds plys one. They are sworn to secrecy about voting. 

The amount of time is takes to elect a pope has been incredibly varied in the past. Several have only lasted one day. Cardinals chose Pope Francis in around two days. However, the longest conclave lasted almost three years - between 1268 and 1271.