Yoga, which is a set of techniques for relaxation, meditation, and muscle control, has been in the news lately. Yoga is practiced in a wide range of religions, but Hindus have been the most enthusiastic.
The relation between Hinduism and Yoga is complicated. It is not just a matter of Hinduism having borrowed techniques from Yoga. The techniques and ideas seem to be part of Hinduism's fundamental religious structure.
Sometimes Yoga is explicitly presented as incompatible with Hinduism. In 2000, the Indian government passed a law that made yoga part of Hinduism. One of the reasons the law was passed was that it defined yoga as a "Hindu religious exercise."
But yoga has been practiced in India for thousands of years. Hindu practice includes eleven different schools of yoga. Hindus consider yoga a central part of Hinduism, and different schools have different ideas about it. The Hindu texts don't mention yoga; they talk about a "union" with god. But "union" and "yoga" mean much the same, and in any case, Hindus don't use the two words as synonyms.
Hinduism and Yoga share many similar ideas. Yoga techniques include breathing exercises, meditation, and body postures. Hinduism teaches that there is a supreme being, and that it is possible to access god directly. But Hindus do not practice yoga to "reach god." Rather, yoga is a method for developing spiritual power.
Hinduism and Yoga also share many differences. Hinduism includes many different gods, and Hindus believe many things that are not part of Yoga. Hinduism includes many practices that Hindus consider inappropriate for Buddhists, Christians, or Muslims (for example, ritual animal sacrifice).