Protestantism is a type of Christian religion. In the United States, a lot of people believe in this religion. Protestantism is different from other types of Christianity, like Catholicism, which is the biggest religion in many different countries. People who practice Protestantism believe that the Bible is the only source of truth, and they also believe that everyone is responsible for their own actions and decisions. They also think that everyone should be able to read the Bible and decide for themselves what is right and wrong. This type of thinking has helped the United States become a place where people with different beliefs can all live together and respect each other.