What is a conclave and how does it pick a new pope?

The coming conclave to choose the next pope is expected to be the largest in the history of the Catholic Church, with 133 cardinal electors slated to gather in the Sistine Chapel. When the papal conclave begins on May 7, 2025, the cardinals of the Roman Catholic Church will enter a cloistered world defined by ritual, reflection, and a carefully controlled daily routine inside Vatican City.