Reformed Churches are a group of Protestant Christian denominations that trace their roots back to the teachings of the Reformation in the 16th century. They emphasize the authority of the Bible, the sovereignty of God, and the importance of faith in Jesus Christ for salvation. Key figures in the Reformation, such as John Calvin and Huldrych Zwingli, played significant roles in shaping Reformed theology. These churches often practice a form of governance that includes elders and deacons, reflecting their belief in a community-oriented faith. Worship services typically focus on preaching, prayer, and the sacraments of baptism and communion. Reformed Churches can be found worldwide, with various denominations such as the Presbyterian and United Church of Christ.