What’s unique about Hinduism?
Hinduism itself is like an open platform such as Android – where philosophers can come and make their own apps (philosophies) and establish their way of thinking (create user base).
A pretty open system – with nobody forced to follow any one school of philosophy. Even atheism and materialism find a place under the umbrella of Hinduism.
Have dealt with three major vedic philosophies in the link below. You may want to check it out: