Bikram, Astanga, Kripalu, Sivananda, Iyengar…while these may sound Greek to most people, they are actually different yoga styles, derived from India more than 5,000 years ago. No longer only for the flower children of the '60s, yoga is now mainstream. There are more than 20 million people in North America practicing yoga as exercise for the mind and body, according to the Yoga Education and Research Center.

But with so many yoga styles available, it may seem like a daunting task for the beginner to tell one from the next. Before you can say "om," seasoned yoga experts explain to WebMD the philosophy of yoga, what the different yoga styles involve, and how you can pick a style that is right for your body—and mind.

The Philosophy
Hatha yoga is the yoga style that is mainly practiced in the U.S., and within it, are many variations, including Bikram and Iyengar. Although these variations differ, each type—no matter the branch or name—is based on the same underlying principle.

"The philosophy of yoga is that it focuses on the combination of body, mind, and spirit," says Elise Browning Miller, MA, a certified Iyengar yoga teacher in Mt. View, Calif., who has been teaching since 1976. "It's connecting with your self on a deeper basis."

Yoga is about quieting the fluctuations of the mind, explains Miller.

For instance, "If you are doing yoga, but you're thinking about work or grocery shopping, it's not yoga—it's exercise," Miller tells WebMD. "With yoga, you need to bring your focus into the present."

It provides a sense of peacefulness and well-being while energizing you at the same time.

"Physically doing the asanas (the yoga poses) is translated as that which is steady and with ease," says Miller. "So there is a stability within the poses and within your mind. Yoga can make you very fit, it conditions your muscles, it energizes you, it helps you breathe, gives you more tone and balance, and more of a feeling of goodness about yourself."

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