All three religions are monotheistic in nature; believing that there is only one God. All three share common roots, and worship the same God, although that God is described or denominated differently in each. Christianity and Islam are missionary religions and seek new followers; Judaism is not a missionary religion and typically discourages conversion.
Judaism is the oldest of the three, and dates its founding to the covenant between God and Abraham; although some scholars date its founding with Moses and the exodus of the Hebrew people from Egypt. Its holy place of worship is normally a Synagogue, although it may be called a Temple. The Jewish Sabbath begins at sundown Friday and ends at sundown on Saturday. Style of worship varies between Orthodox and Reformed Jews, although almost all involve the reading of the Holy Scriptures and the Torah, or Jewish law. Judaism also advocates observance of strict dietary laws, and suggests limiting consumption to foods that are kosher (pure.)
Christianity traces its founding to the ministry of Jesus of Nazareth, although many scholars date it later to the preaching of Paul of Tarsus. The Holy Scriptures of Judaism are the Old Testament of Christianity which has been supplemented by a New Testament which discusses the life and teachings of Jesus. Christian houses of worship are normally denominated Churches. Although there is a great deal of variation in Christian worship, all to some degree borrow heavily from Roman traditions, following the adoption of Christianity by Constantine and many other Roman Emperors. This includes the burning of candles, robes, and liturgical recitation. Candles are not present in Jewish worship, as fire in the synagogue is considered offensive. The Christian day of worship is Sunday, which most Christians denominate as the Sabbath. This also is adopted from old Roman culture, as Constantine, the first Roman Christian emperor, previously worshiped the Sun as the god Sol Invictus. There are no restrictions on diet for Christians.
Islam is the youngest of the three religions, founded by the Prophet Muhammad, who claimed to receive visions from the angel Jebreel (Gabriel.) It's founding date is normally considered the date of Muhammad's hegira (flight) from Mecca, in 622 C.E. Islam teaches that there is only one God, (known as Allah) that there will be a day of judgement for which all devout Muslims should prepare. The typical day of worship and prayer for Muslims is Friday. The house of worship is known as a Mosque. All Muslims are to pray five times a day, and make a pilgrimage to Mecca during their lifetime if they are financially able. Worship services also vary dependent on Shia and Sunni mosques, but typically involve prayer, a sermon and no music. Islam's holy book is the Koran, which incorporates element of the Jewish and Christian scriptures, plus the sayings of Muhammad. Islam also has dietary laws somewhat similar to those of Judaism. Food properly prepared is known as halal. Both Jews and Muslims share a common dietary restriction in that both are to avoid eating pork.
Larrygates provided a good answer.
I would also add that the three religions are termed Abrahamic religions because they have the same roots. All claim Jerusalem as a holy site.
Islam emphasizes the 5 Pillars of Islam. The Qur'an is written in Arabic, and while it may be translated, it is considered to be pure in meaning only in Arabic.
Christianity emphasizes the 10 Commandments. Christianity is heavility divided: originally, it consisted solely of what we know now as Roman Catholicism, but there are now many denominations. Considering all of them, Christianity is the largest religion in the world. Some Christians, specifically Catholics, observe Lent, where they abstain from meat on Fridays in the weeks leading up to Easter.
Judaism uses the Torah, which is noted by Christians to be part of the Old Testament of the Bible. Judaism can also be divided into two larger groups: those who descend from European Jews and are mostly associated with the Yiddish language; and those who descend from Israel and surrounding areas, and are associated with the Hebrew language.