For Hindus, there is no single book to follow. Hindus have the Vedas, Upanishads, Puranas, and Gita. The books Smriti and Sruti are oral scriptures. A quote from the Upanishad is “Of everything he is the inmost Self. He is the truth; he is the Self supreme”. Every religion has a book.
How Many Years have they existed? The religion,Christianity, started a long time ago, about 2000 years ago, but Hinduism started a long time before that. People say Hinduism started in 1500 BCE. Christianity is one of the world's biggest religions, with about 2.2 billion people that follow it worldwide. Although Hinduism is older, it doesn’t have many more followers. Hinduism has a little more than 1.08 billion followers worldwide (15% of world's population) with about 95% living in India. 31.5% of the world are Christians. Isn’t it interesting how Christianity has more followers than Hinduism, even though Hinduism is older.
How much of each religion exists in Singapore? Hindus made up about 5.1% of the residents in Singapore in 2010. Since 2010 things have different, especially the number of people in Singapore. The population in Singapore has gone from 5 million in 2005 to 5.5 million in 2016. Christianity is 18.8% of the religion is Singapore this year. Although in 2010 it was 18.3%. So both religions have almost maintained their numbers even though the population changed.