By the way top ten most does not promote religious beliefs , if one our writers do write something about religion it is his predicament. Besides why fight over religion they basically preach the same thing; do good unto other and love one another. =)
Let's start from the least to the one with the most members.
10.Shintoism- With 4 million followers. It is the indigenous spirituality of Japan. Shinto in English literally means "The way of the Gods" , it is a disorganized religion anyone practicing Shinto are also Buddhists. It is an undefined religion since Shinto practices are already a way of life rather than a belief. They believe in deities that are human like, sometimes animistic figure, they are called Kami's or Gods. Of course they also believe in spirits of trees, mountains etc.... Anyway to give you a clearer picture of what it is, a lot of Japanese anime are mostly based on Shintoism like Yu yu hakusho, InoYasha, Hell teacher Nobe, Dragon Ball, Deathnote has influence of Shintoism mythology.
(Symbol of Jainism)
9.Jainism- With 4.2 million followers. No, no, no... it's not Adolf Hitlers religion, this symbol actually came from Hinduism, it represents goodness, eternal and strength. Befitting to the ones greatest military power in the world Germany. But in Jainism the swastika is a symbol of rebirth and the four types of beings that one can be born into: heavenly, human, animal or hellish. Three dots are displayed over the swastika, which represents right knowledge, right faith, and right conduct. It is these concepts that help a soul eventually escape the cycle of reincarnation altogether, which is the goal of Jainism. Jainism in general stands for peace and none violence. 
8.Confucianism- With 6.3 million followers. Confused? Try Confucianism, just kidding. Well Confucianism has some really powerful proverbs, that's pretty popular in the Western world. Like; "Give a man a fish and feed him for a day, but teach a man how to fish and feed him forever."
Confucianism, in a nutshell; is about personal worth, and striving to fulfill oneself and being the best person one can be in any given situation. =)
7.Bahaism- With 7 million followers. Ever heard of of Bahaism before? It's a religion that's in Persia, they believe that God sends messengers to humanity, the messangers include Jesus Christ, Muhammad and Budha. They believe in unity of religion and unity of mankind.
6.Judaism-With 14 million followers. This religion is actually hard to define, firstly some Jews don't even consider Judaism a religion. Some if not most believe that they are the chosen people of God to be the role model of humanity, and that their ancestors were part of the great travel from Egypt. Well personally I don't know about that, them being chosen and all, they might. Only God knows. =)
5.Sikihism- With 23 million followers. Have you ever wondered what's the religion of those Indians with turbans and thick beards? No they are not Alkaida, most of them are Sikh. It is the belief that all men are created equal and just like the other religion in the countdown, they believe in only one true God, He Who is almighty and all knowing.
4.Buddhism- With 376 million followers. Buddha explained that all our problems and suffering arise from confused and negative states of mind, and that all our happiness and good fortune arise from peaceful and positive states of mind through medidating. Sounds like weed. =) just kidding Lol. Anyway Buddha came 500 years before Christ and does not have a concept of God. You can actually practice Buddhism while having a concept of God.
3.Hinduism-With 900 million followers. Don't confuse yourself from Buddhism and Hinduism, although there are similarities like the belief of Karma and transmigration of souls and the cycle of births and deaths. Hinduism is the religion of the majority of people in India and Nepal. It also exists among significant populations outside of the sub continent. Unlike most other religions, Hinduism has no single founder, no single scripture, and no commonly agreed set of teachings.
2.Islam-With 1.5 billion followers. For the last time Muslims are not terrorists,okay? I've received numerous emails that I should write on how evil Islam is please STOP. The problem with Islam is they don't have a single governing body that explains the Koran, and some scriptures in the Koran are a little abrasive that if you focus on them they might lead you to a path of violence, as you may already know Muslims believe in Allah the merciful, his the same God that Christians and Jews refer to and probably any other monotheistic (religions that believe in one almighty God) religion in the world.
1.Christianity- Christians are 2.1 billion. That is 33.1% of the worlds population. They believe that God sent his only begotten son Jesus Christ to the world redeem mankind of it's sins.What can I say about this religion aside from me being part of it,.. well the Church is not perfect and there are rifts between sects of Christianity. But all the same they follow one book and that's the bible.
I'm done here thank you for reading.
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