The Yoga Sutras are built on a foundation of the Bhagavad Gita. In the Yoga Sutras, Patanjali prescribes adherence to eight "limbs" or steps (the sum of which constitute "Ashtanga Yoga",) to quiet one's mind and merge with the infinite.
What are Astanga Yogas ?
Yama, Niyama, Asana, Pranayama, Pratyahara, Dharana, Dhyana and Samadhi.
Ashtanga yoga consists of the following levels:
1. Yama = abstentions (Abstention is the practice of refraining from something)
These are 5 in number
• ahimsa = abstention from violence = non-violence to all beings
• satya = abstention from lying = truth
• asteya = abstention from theft
• brahma charya = abstention from sexual activity
• aparigraha = abstention from possessions
2. Niyama = observances
These also are 5 in number:
• Saucha = purity
• Santosha = contentment
• Tapas = austerities
• Svadhyaya = study
• Ishvarapranidhana = surrender to God
3. Asana - Postures of the body
4. Pranayama - Control of prana or vital breath
5. Pratyahara - Abstraction; "is that by which the senses do not come into contact with their objects
6. Dharana - Fixing the attention on a single object; concentration
7. Dhyana - Meditation
8. Samadhi - Super-conscious state or trance