How does a Papal Conclave work?

Cardinals leave at the end of a Mass on the eighth of nine days of mourning for Pope Francis. Credit: AAP / Alessandra Tarantino/AP

Cardinals have been meeting in the Vatican ahead of the conclave on 7 May, where they will start to vote for a successor to Pope Francis. Preparations for the centuries-old tradition are underway, following Pope Francis' death on 21 April at age 88.

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