For more about Yoga

Yoga is the integration of Body, Mind and Intellect. All work carried out by any individual in this condition is truly 'Yagna' or work with the attitude of sacrifice. The first step in Yoga is the physical or external Yoga. Under the Ashtanga Yoga of Patanjali these practices will make the body capable of going forward to the higher steps of Yoga.

The higher steps are also classified as internal Yoga.

For more about Yoga visit the site of 

Yogacharya B. Sharma.