Simply put, a conclave is the assembly of cardinals that elects a pope. The word itself comes from the Latin "com" and "clavis," meaning "together" and "key," respectively – highlighting the absolute, behind-closed-doors secrecy with which the cardinals conduct their discussions and balloting.

The reign of Pope Francis is over, and as the Catholic Church mourns his death, it is also looking to the future. Soon after Saturday's funeral, a papal conclave must be held to choose his successor,

A papal conclave, the election of a new pope, tends to begin 15-20 days after a papal vacancy. Black or white smoke indicates each day's decision.