Muslims believe that God revealed the Qur'an to Muhammad, God's final prophet, through the angel Gabriel.
Muslims do not regard Muhammad as the founder of a new religion, but as the restorer of the original faith of Abraham, Moses and Jesus.
Muslims respect Jesus and acknowledge him as an important prophet but he is not elevated to the status of God like has been done in other faiths.
Sunni or Shi'a?
Approximately 85% of the world's Muslims are Sunni and approximately 15% are Shi'a.
God did not specify any particular leaders to succeed Muhammad so Caliph leaders were elected, the Sunni believe these to be the rightful successors of Muhammed.
The Shi'a on the other hand don't quite agree. They believe Muhammad's cousin and son-in-law was the rightful successor. They now follow Imam leaders who they believe hold absolute spiritual control over muslims.