Ashtanga Yoga [अष्टाङ्गयोग] Eight Limbs of Yoga
Abstaining from harming others by controlling body, mind, speech and actions [by self restraint].
The five commandments of yama
1.1. Ahimsaa [अहिंसा ] Non Violence
Ahimsaa is the total absence of any form of hurt or injury to any living being either through thought, words, deeds, etc.. In other words love for entire creation is ahimsaa.
1.2. Satya [सत्य ] Truth
Being truthful in mind and speech, to retain in mind just as seen, heard, inferred and to speak it in the same way accordingly.
1.3. Asteya [अस्तेय] Non-stealing
Not to steal anything and not to be greedy to possess other's wealth, or without earning etc..
1.4. Brahmacharya [ब्रह्मचर्य ] Chastity
To keep one's sense organs, including the organs of procreation, under control and not to be tempted by the lustful enjoyments through thought, words and deeds; And engage in the study and practice of dharma [cosmic law of nature & ethical precepts].
1.5. Aparigraha [अपरिग्रह] Non-covetousness
Avoidance of hoarding wealth, riches, useless things and any materials of enjoyment due to greed.
2. Niyama [नियम] Rules of Conduct
Principles for our own daily lives. Obedience to rules of conduct.
2.1. Shaucha [शौच] Cleanliness
Maintain purity and hygiene of body and mind. Shaucha of body maintained by regular bath, removing toxins from body by asanas, aerating lungs and oxygenating blood by pranayama, and nourishing by balanced nutritious food.
Maintain shaucha of mind by rejecting disturbing emotions like desire [काम kaama], anger [क्रोध krodha], greed [लोभ lobha], delusion [मोह moha], arrogance [मदा madaa], jealousy [मात्सर्य maatsarya], selfishness [स्वार्थ svaartha], unlawful action [अन्याय anyaaya], cruelty [अमानत्व amaanatva] and ego [अहङ्कार ahankaara].
2.2. Santosha [संतोष] Contentment
Satisfaction with and enjoying whatever is attained by fair means.
2.3. Tapas [तपस्] Penance/Austerity
Practice of keeping the mind detached, under control; and experience pleasure and pain, heat and cold, hunger and thirst with equanimity.
2.4. Swadhyaya [स्वाध्याय] Self Study
Study of spiritual books to gain knowledge of reality and spend time in satsang [company of wise people] , with sages and good people and exchange ideas with them.
2.5. Eshwara pranidhaana [ईश्वर प्रणिधान] Regular prayers
Remember Devine [God] and surrender everything to the divine.
Yama is to universal application, niyama is to individual discipline.
3. Aasana [आसन] Posture
Aasanas are helpful in the control of mind and vital elements of body. This removes our physical sufferings, keep our body free from disease. By these, one can control the external and internal organs in the body, and improve concentration of the chitha [mind].
4. Praanaayaama [प्राणायाम] Breath Control
Praanaayaama influences oxygenation of blood, entire nervous system and helps reduce worldly desires and improves concentration of mind.
In other words, praanaayaama is mastering and enlivening the life force.
Breath control is - Shwaasaayaama [श्वसायाम]
5. Pratyaahaara [प्रत्याहार] Inner reflection
The withdrawal of the senses from their respective outside objects and projecting them inwards is pratyaahaara. This requires very strong determination and repression of the senses. Practicing pratyaahaara brings the senses under control, mind of the practitioner not disturbed by the worldly objects.
6. Dhaarana [धारणा] Concention
Fixing one's mind on an external object, like heart, nose or a deity is dhaarana. Here one is concentrated wholly on a single point or on a task in which he is completely engrossed.
7. Dhyaana [ध्यान] Meditation
Meditating with constant attention on the object of concentration. Dhyana purifies the mind of rajas and tamas gunas and lightens the mind with sattva guna.
8. Samaadhi [समाधि] Liberation, enlightenment
State of super-consciousness and perfect calm.