Yoga emphasizes breathing correctly (the Yogic full breath using the diaphragm). We substantially increase the intake of oxygen through deep inhalation and release the toxins appropriately through our deep exhalation.
Yoga teaches us to be constantly aware of our breathing patterns, and to breathe consciously in our daily life. Specific breathing techniques (pranayama) are devised to further purify the nadis, balance the breath and the energy in our system, and to store and channel the subtle energy (prana) for higher purposes.
The word Hatha is composed of the words Ha and Tha, which mean sun and moon, respectively. This refers to the balance between the prana vayu (the positive vital air) and apana vayu (the negative vital air).
Prana (vital air) in the body of the individual is a part of the universal breath. The regulation of the harmonized breath helps the Yogi to regulate and steady the mind. Pranayama needs to be practiced by all serious Yoga practitioners. Advanced practices need to be done only by those already practicing a pure lifestyle, and it is recommended that you put yourself under the supervision of a teacher in a pure environment, like an ashram.