Protestants are members of a branch of Christianity that originated in the 16th century during the Reformation. This movement sought to reform the practices and beliefs of the Roman Catholic Church, leading to the establishment of various denominations. Key figures, such as Martin Luther and John Calvin, emphasized the importance of scripture and faith in salvation. Protestantism encompasses a wide range of denominations, including Baptists, Methodists, and Lutherans. These groups often differ in beliefs and practices but share core principles, such as the authority of the Bible and the priesthood of all believers.