Yoga
Yoga has quickly become very popular in the western world. Hatha Yoga in particular, with its emphasis on Asana (postures) has become a new exercise fad, with Power Yoga the new aerobics. Although there are many yoga studios that attempt to preserve the spiritual content and teach the eight original limbs of yoga, there seems to be a large misconception that yoga is nothing more than postures and stretching. Yoga is in fact an entire lifestyle, the postures only being one of the eight limbs of one particular path. There are four main paths of Yoga, Raja being the only path that is well known to the west. The other three are Karma Yoga, Bhakti Yoga, and Jnana Yoga. In the West, when one says they practice Yoga, it usually means they practice Hatha Yoga (part of the Raja family). But in India, when one says "I practice Yoga," it is the same as saying "I practice Religion." It is a spiritual life that ideally includes all of the paths of Yoga as stepping stones toward enlightenment.
Raja Yoga
Karma Yoga
Bhakti Yoga
Jnana Yoga
Introduction to the Yoga Sutras by Swami Venkatesananda
Yoga Sutras of Patanjali
Yoga Links
A personal insight
*Note to the reader regarding the Yoga Sutras of Patanjali : The link provided here is but one link to one translation of the Yoga Sutras. If you were to compare different translations, you would find that they can vary drastically in interpretation. Because of this I would discourage the reader from placing too much value on any one interpretation. For added insight, I highly recommend Swami Venkatesananda's Introduction.
"A yoga is a method--any one of many--by which an individual may become united with the Godhead, the Reality which underlies this apparent, ephemeral universe."
-Patanjali