Buddhism is not a unified organization so that there is a single hierarchy of leadership. Each sect has its own leaders and important persons.
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Buddha developed the teachings and process of allowing humans to escape suffering and the cycle of death and rebirth that were later called Buddhism.
Buddhism is not a monolithic organization. Each school or tradition, and there are dozens, would regard its founder, significant teachers or present leader in the positions of "the top three".
In Buddhism, humans are considered just one sentient life form among many others. However, humans have the special status of being the one life form who can obtain enlightenment in the way of Buddha. Humans have a reason to find Dharma, and the means to follow it.
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Buddhism was and still is based on insight into human nature. Since humans have a tendency to believe in gods, gods get mentioned in early Buddhism and later get incorporated from local religions in the areas Buddhism spread to. At its base, Buddhism is about working with what we can know and see directly, and on seeing through delusion, not on developing beliefs in things unseen, or feeding delusion.
Buddhism isn't into the wish or prayer granting business. Gods and supernatural beings do that, Buddha is neither of those, he is a man. Buddhism does not see gods or deities as interacting with humans.
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The top three religions are Christianity, Islam and Hinduism. Atheists and secular people may appear in the top three spots in some tables. Buddhism (at 500 million) is usually 3rd or 4th.
Hinduism, Islam, Sikkhism, Buddhism and Jainism.
Confucianism has only One God. Buddhism believes in numerous deities. Confucianism is from China. Buddhism is from India.
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