Answer:
Joseph Smith had several visions and visitations. His first vision occurred when he was 14, in 1820. He went into the woods near his home to pray. He wanted to ask God which church he should join, since members of his family were going to several different denominations at the time. God the Father and Jesus Christ appeared to him in the woods and told him to join none of them because none of them were entirely true, and that it would later be revealed to him how to set up the true church of Jesus Christ.
Joseph then went several years without receiving any visions. When he was 17, in 1823, he was praying one night before bed for forgiveness of his sins when an angel appeared by his bedside. This angel called himself Moroni and told Joseph there was a gold plates buried in a hill near his house and that he would later translate these. Each year for the next 4 years, Joseph went to the place where these plates were buried and receive further instruction from the angel Moroni until he was finally allowed to take them home.
While translating the plates into the Book of Mormon, and after the church's founding in 1830, Joseph received visitations from numerous Biblical characters, and several more visits from Moroni. These men taught him the Gospel and gave him priesthood authority. They include Peter, James, John, Adam, Elijah, John the Baptist, and others. Jesus Christ also visited Joseph several times during this period. The things that were revealed to Joseph by Jesus Christ are recorded in a book called "The Doctrine and Covenants."
If you would like to learn more about Joseph Smith or about the Church of Jesus Christ of Latter Day Saints (commonly known as Mormons), please visit the links provided below under "related links".