Answer:
Simply put, the Catholic Church used to sell "indulgences" that people could buy to pay for their sins. Some people, including the theologian Martin Luther, didn't think this was right. They believed this was a corrupt practice. So, they started a movement to reform the Church and end the sale of indulgences. The result was the Protestant Reformation. Martin Luther's "Ninety-Five Theses" started the movement and spread ideas to all of Europe through a new printing press technology. The movement gained momentum, and people began questioning other practices of the Church. Eventually, this led to the formation of new Protestant denominations, including Lutheranism, Calvinism, and Anglicanism. These denominations emphasized personal relationships with God, personal interpretation of Scripture, and reforms in worship and theology. The impact of the Reformation is still felt today.