The Vatican announced this week that its College of Cardinals will convene on May 7 for the conclave process at the famed Sistine Chapel – where they'll elect Pope Francis' successor as leader of the Roman Catholic Church. Francis, the 266th pontiff in the church's nearly 2000-year history, was interred over the weekend in the Basilica of St. Mary Major after a funeral service that drew dozens of global leaders and an estimated 400,000 mourners. In the interim, the College of Cardinals is the acting head of the church. But the man who succeeds Francis will preside over a religious body comprising nearly 18% of the world's population, according to the University of California's Dornsife College of Letters, Arts and Sciences. But what do Catholics believe? How do they differ from other Christians? Here's what to know. Are Catholics Christian? All Roman Catholics are Christians, but not the other way around. Christianity, according to Britannica.com, is a world religion rooted in the life, teachings and death of Jesus Christ, and Roman Catholicism is the largest of its three most significant offshoots. In general, the reference site states, Roman Catholics veer from other branches of Christianity in their beliefs about the sacraments and the importance of the papacy, in addition to a focus on the saints and the Virgin Mary. The church recognizes sacraments, or important rituals and processes, such as baptism and matrimony. What is a saint? Saints are persons in heaven who were officially canonized or not who did one of the following, according to the United States Conference of Catholic Bishops: Lived heroically virtuous lives.Offered their life to others.Died for their faith. All saints must have lived lives worthy of imitation. When was Roman Catholicism founded? According to Britannica.com, Roman Catholicism traces back to the life and teachings of Jesus Christ in Roman-occupied Jewish Palestine around the year 30. Roman Catholicism became the official religion of the Roman Empire in the year 380, according to Learn Religions, a reference site produced by full-time ministers, published authors, licensed clergy and teachers. The religion would experience two major splits, first in 1054 with the Eastern Orthodox Church and then again with the 16th-century Protestant Reformation. How many Catholics are in the world? There are an estimated 1.4 billion Catholic adherents around the world. The Catholic News Agency earlier this year reported a slight increase in the number of Catholics globally, with the population growing to 1.406 billion in 2023 from 1.39 billion in 2022. Much of the growth is happening in Africa, where the number of Catholics climbed more than 3%, from 272 million in 2022 to 281 million in 2023, the news agency said. The Americas account for nearly 48% of the world’s Catholics, according to Vatican News. What do Catholics believe about the pope? Catholics believe that each pope, the bishop of Rome, is a successor to the throne held by Saint Peter, with authority over the church, according to Britannica. Early church fathers recognized the apostle Peter as the person to whom Jesus Christ intended to pass his authority when he said, “You are Peter and upon this rock I will build my Church.” They also believe that Peter moved to Rome and was martyred there under the emperor Nero, though that is contested by some Protestants. Catholics believe in the pope’s authority to ensure the continuity of church teachings and Catholic unity worldwide. For Catholics, the pope acts as a moral compass by speaking out on matters of faith and principles; Francis focused on social justice and reaching out to marginalized communities. Contributing: Julia Gomez