Ashtanga Yoga is an ancient system of Yoga that was taught by Vamana Rishi in the Yoga Korunta. This text was imparted to Sri T. Krishnamacharya in the early 1900’s by his Guru Rama Mohan Brahmachari, and was later passed down to Pattabhi Jois during the duration of his studies with Krishnamacharya, beginning in 1927.
The following are aspects that Pattabhi Jois emphasizes as the main components of Ashtanga Yoga.
Vinyasa: Vinyasa means breathing and movement system. The Vinyasa provides internal purification that keeps the body healthy.
Tristhana: This means the three places of attention or action: posture, breathing system and looking place (drishti). These three are very important for yoga practice, and cover three levels of purification: the body, nervous system and mind. They are always performed in conjunction with each other.
Asanas purify, strengthen and give flexibility to the body. Breathing is rechaka and puraka, that means inhale and exhale. Both the inhale and exhale should be steady and even, the length of the inhale should be the same length as the exhale. Breathing in this manner purifies the nervous system. Dristhi is the place where you look while in the asana. There are nine dristhis: the nose, between the eyebrows, navel, thumb, hands, feet, up, right side and left side. Dristhi purifies and stabilizes the functioning of the mind.
An important component of the breathing system is mula and uddiyana bandha. These are internal practices that seal in energy, give lightness, strength and health to the body, and help to build a strong internal fire. Without bandhas, breathing will not be correct, and the asanas will give no benefit. When mula bandha is perfect, mind control is automatic.
The six poisons: A vital aspect of internal purification that Pattabhi Jois teaches relates to the six poisons that surround the spiritual heart. These are desire, anger, delusion, greed, envy and sloth. When yoga practice is sustained with great diligence and dedication over a long period of time, the heat generated from it burns away these poisons, and the light of our inner nature shines forth.
This information is from KPJAYI.