There are many kinds of religions in this World like Islam, Buddhism , Sikhism, Judaism, Zoroastrianism etc. All these religions are having unique characteristics.
Christianity traces it's origin from Judaism in the 1st century C.E. This religion is based on the life and teachings of Jesus Christ. Jesus life and his teachings are described in the Holy Book namely Bible.
Judaism is the mother of Christianity and Islam. It is based on the messages of God revealed to the Prophet Abraham and Moses.
Similar is the case of Islam. Islam is essentially based on the life and teachings of Prophet Mohammed. All the teachings of God, which were revealed to Prophet Mohammed, were codified in Holy Quran.
Similar is the case of Buddhism, Jainism, Sikhism, Zoroastrianism.
Buddhism, Jainism, Sikhism and Zoroastrianism etc. All these religions are based on the life and teachings of Gautam Buddha, Mahavir, Guru Nanak, Zarathustra etc.
Teachings of Prophet Abraham, Moses, Jesus Christ, Prophet Mohammed, Buddha, Mahavir, Guru Nanak, Zarathustra etc were codified in holy books and respective Holy Book are those are considered to be wisdom of God revealed to their respective prophets in the respective religion.
If we compare Hinduism with that perspective, then all these elements are missing.As we have seen that Judaism, Christanity, Islam, Sikhism, Zoroastrianism.
Buddhism, Jainism, Sikhism and Zoroastrianism etc are all based on the life and teachings of Prophet Abraham, Moses, Jesus Christ, Prophet Mohammed, Gautam Buddha, Mahavir, Guru Nanak, Zarathustra etc. Each religion has one holy man and all of his teachings codified in Holy Book.
Even life and teachings of Prophet Abraham, Moses, Jesus Christ, Prophet Mohammed, Gautam Buddha, Mahavir, Guru Nanak, Zarathustra etc are having historical proof. These religions are organised. They all are having unique way of worshipping, unique place for worshipping.
Such is not the case of Hinduism is. Hinduism is not based on any individual man or any individual codified books. Neither it is organised one. People can worship as per his own choice. There is no any kind of compulsion at all.
There has been many enlightened persons from the ages , who shared their experiences with their followerers. These sages used to impart their knowledge to their followers in forest who inherited these wisdom from their ancestors. That's how the accumulated wisdom cotinued from generation to generation.
Shiva, Vishnu, Krishna , Ganesha etc are in numerous deities, whom people worship as per their own choice and orientation. But there is no any historical proof of existence of Shiva, Vishnu, Krishna , Ganesha etc as such.
Even people follow teachings of Ramayana, Mahabharata, Upnishad, Puran etc, but there is no any codified teachings in the sense other religions have.
Enlightened persons in India never bothered about time, space and their teachings. If someone asks, whom hindu worshipped 2000 years back, then answer would be self. The real moto of Indian Masters to attain salvation.
Many method have been prescribed by Indian Masters. Worshipping, Learning, Yoga, Meditation , Tantra etc are all path of attaining salvation. In fact hinduism is a way of life, which provides different method to people of different kind, to attain salvation and merge in the ultimate supreme.