Yama is the first of the eight limbs of yoga outlined in the yoga sutras. Yama is also sometimes called “the five restraints” because it describes what one should avoid to advance on the spiritual path.

There are five types of Yam :

Ahinsa: Non-violence or harmlessness. This cannot always be practiced literally since it is not always possible in the normal course of living. Even washing one’s hands kills bacteria. To perfect ahinsa one must not wish harm on any creature.
Satya: Non-lying or truthfulness. This doesn’t mean to be tactless, but to always tell the highest truth. It is in the “restraints” category because if one restrains oneself from wishing things were other than they are, one will always tell the truth.
Asteya: Non-covetousness. Not wishing for more than one has, or for what another has.
Brahmacharya: Sexual self-restraint. Literally means “flowing with Bramha.” This is often translated as celibacy, but can also just be taken as sexual self-control, or overcoming sexual desire. According to the yoga sutras, this practice will give one great mental and physical stamina because it prevents one’s energy from being expended in sexuality. Self control in all things is the direction of true growth.

The other meaning of Brahmcharya is Self-control, Self -discipline, Creating new good habits, and removing bad habits 
Aparigraha: Non-possessiveness. Letting go of all attachment to one’s possessions, including one’s body, and being willing to relinquish them all at a moment’s notice.

External Limbs

  1. Yam
  2. Niyam
  3. Asan
  4. Pranayam

Internal Limbs

  1. Pratyahaar
  2. Dharna
  3. Dhyan (Meditation)
  4. Samadhi