The term Yoga has a very broad scope. There are several schools or systems of Yoga. Dnyanayoga (Yoga through knowledge), Bhaktiyoga (Yoga through devotion), Karmayoga (Yoga through action), Rajayoga (Royal or supreme Yoga) and Hathayoga (Yoga by balancing opposite principles of body). All of these schools of Yoga are not necessarily very different from each other. They are rather like threads of the same cloth, entangled into each other. For thousands of years, Yoga has been looked upon as an effective way of self-improvement and spiritual enlightenment. All these systems essentially have this same purpose; only the ways of achieving it are little different for each of them. In its most popular form, the term Yoga has come to associate with the last of these systems which is Hathayoga.
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