Over the next four days, electors will be allowed to vote up to four times a day to determine who will be the next pope. In order for a new pope to be elected 77 of the 115 Cardinals must vote for a single candidate.
"We implore the Lord, that through the pastoral solitude of the Cardinal Fathers, He may soon grant another Good Shepherd to his holy church," said Cardinal Angelo Sodan.
Pope Benedict XVI was the first pope to resign in 600 years.
The last pope to abdicate was Pope Saint Celestine V who abdicated in 1294. So as you can see it's a rare occurrence.
Cardinals prayed for divine guidance before the event. The papal conclave is made up of 115 Cardinals from the ends of the earth. Each one is taking into account the delicate situation that they are having to endure right now as the Catholic Church waits with bated breath.