Mormonism is a type of religion that some people follow. It began in the 1800s by a man named Joseph Smith, who said he had a vision from God. Mormons believe in God, Jesus Christ, and the Bible. They also have an additional book called the Book of Mormon that they believe is also scripture.
Polygamy is when one person has more than one spouse at the same time. This used to be something that some Mormons did, but it is no longer allowed by the church. Polygamy was stopped because it was against the law and caused problems for families.
Mormons today follow the teachings of the church leaders, who say that having more than one spouse is not allowed. It is important to remember that not all Mormons practice or support polygamy.