Reformed Christianity is a branch of Protestantism that emerged in the 16th century during the Reformation. It emphasizes the sovereignty of God, the authority of Scripture, and the necessity of grace through faith. Key figures include John Calvin and Huldrych Zwingli, who shaped its theological foundations, particularly in areas like predestination and the sacraments. Reformed Christians often adhere to confessions and catechisms, such as the Westminster Confession of Faith, which outline their beliefs. Worship in Reformed churches typically focuses on preaching, prayer, and the reading of Scripture, reflecting their commitment to a biblically-centered faith and community life.