Islam is divided into two categories. Think of Islam as a tree. You have the roots of religion, without roots a tree cannot grow, and then the branches of Islam, without which there will be no beauty.
We will start by explaining the roots of religion. There are 5. They are called the Usool-e-Deen.
1. Tauheed
Tauheed refers to the oneness of Allah. It means there is no God other then Allah . He isn't the son of anyone, nor is anyone His son. He does not have a family, he is alone and one.
2. Adalat
Adalat refers to the justice of Allah. He is just to everyone and everything. Some people tend to believe that everything we do in our life is because Allah has pre-planned it for us, though this is not the case; and shows great injustice and gives man no choice to make decisions between the right and wrong. It may seem to us sometimes that injustice is being done to us or others, but this is not the case, rather it is our lack of knowledge and understanding.
3. Nabuwat
Nabuwat means Prophethood. Muslims must believe in the concept of Prophethood, and that there were about 124, 000 Prophets sent down on earth to guide us. All the Prophets were sinless, and all preached the correct message, from the time of Hazrat Adam (as) till the last and final Prophet; Muhammad (PBUH).
Prophethood is divided into Nabi and Rasool. Every Rasool (Apostles) is a Nabi (Messenger), but not all Ambiya (Plural of Nabi) are Rusul (Plural of Rasool). A Rasool brings divine law, and a Nabi continues the message of the Rasool before him.
4. Imamat
Just like Prophethood is in the hands of Allah (swt), same is the case with Imamat. An Imam is a leader. Muslims believe that there were 12 Aaima (Plural of Imam) after the Prophet Muhammad (PBUH). An Imam does not bring new law or rulings, but continues the message of the last and final Prophet. The Imams were also sinless, and did not make mistakes. The Aaima have authority over us as our leader, and we have to obey them, just like we obey Allah and his Messengers.
O ye who believe! Obey Allah, and obey the messenger and those of you who are in authority; and if ye have a dispute concerning any matter, refer it to Allah and the messenger if ye are (in truth) believers in Allah and the Last Day. That is better and more seemly in the end. (4:59)
5. Qiyamat
Last but not least, the concept of Qiyamat; the Day of Judgment. Every Muslim must believe in the Day of Resurrection, where all human beings will be judged according to their deeds. People will either be rewarded for their good deeds, or punished for their evil deeds.
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Now we will take a quick definition-type look at the branches of Islam. The Firo-e-Deen. They are 10 in number.
Namaz: Praying; 5 times a day.
Roza: Fasting, in the month of Ramadhan
Hajj: Making pilgrimage to the Holy city of Makkah, atleast once in their lifetime; whenever given the chance.
Zakat: Islamic tax, given from one's wealth to the poor and needy.
Khums: Islamic tax; one-fifth of certain items which a person acquires as wealth, and which must be paid as an Islamic tax.
Jihad: To struggle, or strive. Jihad is divided into two. Jihad-e-Akbar (Major Jihad) and Jihad-e-Asghar (Minor Jihad). Major Jihad involves fighting against one's desires, where as the Minor Jihad involves fighting against the enemies of Islam when attacked upon first.
Amar-bil-Maroof: Means to enjoin in what is good and telling or asking others to enjoin in good.
Nahi-anil-Munkar: Staying away from evil, and telling or asking others to stay away from evil.
Tawalla: To love the Ahlul Bayt and their followers.
Tabarra: To disassociate from the enemies of Ahlul Bayt
source : sibtayn
