After Muhammad's name Muslim people recite a small prayer asking God to bless him and give him peace. This is often shortened to PBUH ( Peace be upon him).
Muhammad (PBUH) was poor, both of his parents died by the time he was six years old. He grew up honest and trustworthy. He did not like conditions where he lived and often went out into the mountains to think about life. One day while he sat and thought, God's messenger the Angel Gabriel came and gave him a message from God. This happened regularly over a period of years. The words sent by God were recorded and are the content of the Qur'an, the Muslim holy book.
All Muslims believe that Islam existed from the day Adam and Eve were sent down to earth. Other prophets were Abraham, Noah, Ismail, Isaac, Joseph, Moses, David, Solomon and Jesus. They all spread the word of God. Muslims believe that Muhammad (PBUH) is the last prophet of God to be sent to the world.
Muhammad started to teach the local community but the people who listened to him were persecuted and eventually forced to leave the area. They all went to Medina. This marks the start of the Islamic calendar because Muhammad (PBUH) founded the first Muslim community there. Their numbers were strong and they were looking for somewhere else to live. There had been some upset in Makkah, the people there had broken the peace treaty (attacking and killing some non-muslim allies in Makkah) and the Muslims consequently marched into Makkah and met no opposition. The people from Makkah became Muslims.
There is no picture of Muhammad (PBUH), Muslims do not worship any image because pictures are of man and they take great care they only worship God who has no image.