The term "Presbyterian" refers to a branch of Protestant Christianity that emphasizes the governance of the church by elders, known as presbyters. This tradition originated in the 16th century during the Reformation, particularly through the teachings of John Calvin. Presbyterians believe in the authority of the Bible and the importance of faith in Jesus Christ for salvation. Presbyterian churches are known for their structured worship services and a strong emphasis on education and community service. They often practice baptism and Holy Communion as sacraments. The Presbyterian Church (U.S.A.) is one of the largest denominations in the United States, with a rich history and diverse congregations.