The Arabic word 'Islam' simply means 'submission', and derives from a word meaning 'peace'. In a religious context it means complete submission to the will of God. 'Mohammedanism' is thus a misnomer because it suggests that Muslims worship Muhammad rather than God. 'Allah' is the Arabic name for God, which is used by Arab Muslims and Christians alike.
Islam is not a new religion, but the same truth that God revealed through all His prophets to every people. For a fifth of the world's population, Islam is both a religion and a complete way of life. Muslims follow a religion of peace, mercy, and forgiveness, and the majority have nothing to do with the extremely grave events which have come to be associated with their faith.
Muslims believe in One, Unique, Incomparable God; in the Angels created by Him; in the prophets through whom His revelations were brought to mankind; in the Day of Judgement and individual accountability for actions; in God's complete authority over human destiny and in life after death. Muslims believe in a chain of prophets starting with Adam and including Noah, Abraham, Ishmael, Isaac, Jacob, Joseph, Job, Moses, Aaron, David, Solomon, Elias, Jonah, John the Baptist, and Jesus, peace be upon them. But God's final message to man, a reconfirmation of the eternal message and a summing-up of all that has gone before was revealed to the Prophet Muhammad through Gabriel.