Eighteen days after Pope Francis last appeared on the balcony of St. Peter's Basilica, his successor -- the 267th pope -- emerged.

A new pope will be selected when a candidate gets a two-thirds-plus-one majority vote by the cardinal electors. White smoke will be sent up the chimney of the Sistine Chapel when that happens, to indicate a new pope has been chosen.

The cardinals at the Sistine Chapel in Vatican City vow to follow the rules of the conclave, the process by which the next pope is chosen.