The Roman Catholic Church is the largest and oldest Christian denomination in the world. Headed by the Pope in the Vatican, the Roman Catholic Church believes that it has an unbroken line from the first century church and is the true church of Christ. There is a wide diversity of beliefs among Catholics but they observe seven sacraments particularly the Eucharist. Some Catholics believe that during the Holy Communion, the bread and wine literally turns into Christ's body and blood. Other common beliefs include penance, the Trinity, existence of purgatory, and the Christian obligation to do good works. The Roman Catholic Church also venerates and reveres Mary, the mother of Jesus.