"I salute the primeval Lord, Siva, who taught to Parvati the Hatha Yoga vidya, which is as a stairway for those who wish to attain the most excellent Raja Yoga."
There is often confusion in people's minds regarding this branch of yoga. Many people think that the term 'hatha yoga' refers only to asanas - or to asanas and pranayama. The goal of practicing asanas and pranayama is the same as for all other forms of yoga sadhana: God-realization. Asanas and pranayama are tools for gaining control of the mind and prana to facilitate the attainment of this goal. Good health, flexible body, decreased stress levels are side-effects.
Asanas and pranayama are only two of the techniques of hatha yoga. The practitioner must also be trying to live his/her own life in accordance with the ethical and moral basis of yoga, as well as practicing meditation. Hatha yoga begins with the physical body. By gaining control of the physical, the practitioner tries to gain control of the prana... and by controlling the prana, one gains control of the mind. For this reason, we say that the teaching of yoga is not a profession; it is a sadhana. A yoga teacher should strive to be humble and to feel that he/she is an instrument for the divine energy. Yoga teaching is based on guru parampara; knowledge is passed from a living teacher to a student in an unbroken chain. A good teacher is also a good student. He/she is able to understand the teachings received from the teacher, practices and then teaches based on direct, personal experience. A yoga teacher is a yoga practitioner, not a preacher.