There is one fundamental difference between the two faiths, such that they can not really be considered to be similar. To Christians, Jesus was the son of God, but to Muslims he was little more than a prophet, like Isaiah on the one hand and Muhammad on the other. The divinity of Jesus is so central to Christianity that, rather than Islam being much the same story, it is a complete denial of the Christian message.
They're similar in the fact that they have one god (Allah in Islam, Yahweh in Christianity.)
Christianity, Islam, Judaism & even Baha'i all have a mutual ancestor: Abraham.
Christianity, Judeaism, and Islam are similar. they believe in the same God and have a shared History. the Story splits with Abraham.
Christianity and Islam have similar religious roots in the Middle East although what was believed about individual characters represented may diverge very greatly. For example, in Christianity Jesus is the savior, but in Islam he is a prophet.
Judaism Christianity and Islam all are...Monotheistic Religions.
Judaism, Christianity, Sikhism, Zoroastrianism, & Baha'i.
Islam, Judaism and Christianity.
Christianity, Islam
Islam, Christianity
Heaven, hell, and a final judgement
Judaism, Christianity, and Islam have all claimed the Holy Land for themselves.
The Bible is to Christianity as the Qur'an (Koran) is to Islam.