There is a lot of similarity between Islam, Judaism and Christianity, all being Abrahamic religions, but there are also large differences. Despite the differences, we all believe in one God, creator of all things, and doing good things and avoiding evil.
One thing to note is that contrary to the Christian belief that faith alone will enter an individual into heaven, not good works, Islam preaches that it is good works and belief that enter one into heaven. Allah, the Arabic word for God which linguistically has been broken down as "Al- Ilah", translating as the One God, says many times in the Qur'an referring to the favoured ones in the afterlife as those who do good works and are believers in Him.
A few important terms in Islam:
Allah- The Arabic name of the one and only creator and sustainer of the heavens and the earth.
Qur'an- Literally recitation, it's the book of Allah's words that were transmitted directly from Allah to Archangel Gabriel to the Prophet Muhammad over a period of 23 years. Muslim belief is that it is solely Allah's word, though only the Arabic, translations aren't perfect.
Muslim- Literally one who submits. Islam means submission to Allah, and the one who adheres to Islam and submits to Allah, is a Muslim. It has no cultural or racial implications, it's completely open to any human being.
Islam is built on five pillars. They are as follow ;
Shahadah (Testimony of faith)
Salat (Five daily prayers)
Fasting the month of Ramadan
Zakat (Paying alms tax or charity)
Hajj (Pilgrimage to the Ka'aba in Makkah)
Shahadah: The first pillar is the most essential requirement of being a Muslim, as there can be no doubt in the belief in one God. The Shahadah is " La ilaha illa Allah, Muhammad ur-rasuul Allah", or in English, There is no true God ( or anything worthy of worship ) except Allah, and Muhammad (SAWS) is the messenger of God. Without this unshakable faith and belief in the heart, there is no Islam. Islam itself translates as peaceful submission, and submission to Allah specifically. When a person makes this statement, and believes it in their heart, they remove all feelings of loyalty, devotion, and most importantly, worship of anything other than Allah Almighty. There's no clergymen to "put in a good word" or "forgive" you, its simply between you and your lord, Allah. This is why when Islam was revealed it was so liberating for the people of the time, as they were slaves to the rich, and this religion broke the chains of slavery to man, or creation, and gave them the freedom of solely worshipping the one creator. Nobody can cause harm or death, or give life except Allah, so worshipping anything other than Him is fruitless and simply delusional.
Salat: The second most important aspect of Islam are the Salat, or the five obligatory daily prayers offered to Allah. These prayers are what keep a Muslim clean of sin and give him/her protection from the temptations of the world, and also five chances to completely connect with Allah and ask him for whatever you need, and to show your appreciation for the blessings he has given you. The prayers are best offered at the beginning of their time, and in congregation, but there is a window for prayer to be offered and still valid. The five prayers are offered as follows;
Fajr is offered at dawn
Dhuhr is offered near noon time
Asr is offered at midday
Maghrib is offered at sunset
Isha is offered late in the evening
Thankfully today there are many timetables available on the internet based on your location. Here is a recommended site; http://www.islamicfinder.org/index.php?lang=english. There are also smartphones apps available as well.
Fasting: The third pillar of Islam is obligatory on every able Muslim, only exempted for the ill or the travelling. Ramadan is the ninth month of the Islamic Hijri calendar, and a very holy one. Muslims are required to pass the 30 days of this month abstaining from food, drink and intimate relations from the time of Fajr, until the time of Maghrib, or from dawn to sunset. There is so much blessing and mercy in this month, it's uncountable. The act of abstinence from food and drink connects people with the poor and weak, who don't have the luxury of food and drink any time they want it. This act makes Muslims sympathetic and have open hearts to the poor and needy. It also increases ones spiritual growth and connection to Allah Almighty.
Zakat: Keeping with the feelings gained during Ramadan, a Muslim also realizes that the money we have on earth doesn't belong to us humans, it really belongs to Allah Almighty. He has given to us in trust, and by that token, Zakat is our responsibility to share that money. It is a specified percentage of money, based off of ones income and assets, that is to be distributed to those in need. This charity does many things, such as helping the one whom it is given to, purifying the money of the one who gives it, and actually encourages growth of your income through blessings from Allah Almighty.
Hajj: The fifth and final pillar of Islam is the Hajj, or pilgrimage to the Holy Ka'aba in Makka. The Ka'aba was built by Prophet Abraham (PBUH), by command of Allah Almighty. This is the house of Allah Almighty, and Muslims are commanded to make pilgrimage to this House in the twelth month of the Islamic calendar, called Dhul-Hijjah. This event is only due from those who have the means to make it, and is only necessary once in a lifetime. The Hajj entails specific rites and rituals to be performed, and it is solely done for the sake of pleasing Allah Almighty. Kings and peasants walk amongst each other around the House with no knowledge or care, because in front of Allah there is no distinction based on class, income or culture. This pilgrimage attracts 2-3 million pilgrims per year.