Islam is the arabs's version of Christianity. The arabs did not have a religion in the 6th century so they decided they should have their own because they did not like the fact that the Jews had their religion and the Christians had theirs and they had none and that was very humiliating for them.
So they invented their own religion mainly by copying bits and pieces from Judaism and Christianity and then called it Islam. Then they made up pieces as they went along over the years and voila instant religion! Now the followers of Islam get very touchy about their religion and they go around trying to convince the world that they are very nice people by showing lots of pictures of children and girls in Islamic dress and when they can, they murder anyone that does not believe them.