Judaism: Judaism believes in only one God, Yahweh, and that he sent his prophets as well as leaders to lead his people to the promise land. They believe in everything in the Old Testament of the Holy Bible, but disregards the beliefs of the New Testament.
Christianity: Christianity takes into account the Old Testament's beliefs of Judaism, but also adds the New Testament. This is also one of the largest religions, and is one of the more diverse one (having different types of "Christianity").
Islam: Islam believes that there is only one God, Allah, and that he sent his messenger, Muhammad, to share the rules set by God. The religion in a sense follows Christianity and Judaism closely, but defers in how to implement what is taught, as well as some other ideas.
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