Adherents hold that Hinduism—one of the principal faiths in the modern world, with about one billion followers—is the world's oldest religion, with complete scriptural texts dating back 3,000 years.
Atheism is not a belief system nor is it a religion.
While there are some religions that are atheistic (certain sects of Buddhism, for example), that does not mean that atheism is a religion.
To put it in a more humorous way: If atheism is a religion, then not collecting stamps is a hobby.
In the U.S., belief in a deity is common even among the religiously unaffiliated – a group composed of those who identify themselves, religiously, as atheist, agnostic or “nothing in particular,” and sometimes referred to, collectively, as religious “nones.” Indeed, nearly three-quarters of religious “nones” (72%)