1- Yama :  Universal morality
2- Niyama :  Personal observances
3- Asanas :  Body postures
4- Pranayama :  Breathing exercises, and control of prana
5- Pratyahara :  Control of the senses
6- Dharana :  Concentration and cultivating inner perceptual awareness
7- Dhyana :  Devotion, Meditation on the Divine
8- Samadhi :  Union with the Divine

1. Yamas (Universal Morality)
The word ahimsa literally mean not to injure or show cruelty to any creature or any person in any way whatsoever. Ahimsa is, however, more than just lack of violence as adapted in yoga. It means kindness, friendliness, and thoughtful consideration of other people and things. It also has to do with our duties and responsibilities too.
Ahimsa implies that in every situation we should adopt a considerate attitude and do no harm.

2-Niyama (Personal Observances)
Niyama means "rules" or "laws."  These are the rules prescribed for personal observance. Like the yamas, the five niyamas are not exercises or actions to be simply studied. They represent far more than an attitude. Compared with the yamas, the niyamas are more intimate and personal.
They refer to the attitude we adopt toward ourselves as we create a code for living soulfully.

3-Asanas (Body postures)
Asana is the practice of physical postures. It is the most commonly known aspect of yoga for those unfamiliar with the other seven limbs of Patanjali’s Yoga Sutra. The practice of moving the body into postures has widespread benefits; of these the most underlying are improved health, strength, balance and flexibility. On a deeper level the practice of asana, which means "staying" or "abiding" in Sanskrit, is used as a tool to calm the mind and move into the inner essence of being. The challenge of poses offers the practitioner the opportunity to explore and control all aspects of their emotions, concentration, intent, faith, and unity between the physical and the ethereal body. Indeed, using asanas to challenge and open the physical body acts as a binding agent to bring one in harmony with all the unseen elements of their being, the forces that shape our lives through our responses to the physical world. Asana then becomes a way of exploring our mental attitudes and strengthening our will as we learn to release and move into the state of grace that comes from creating balance between our material world and spiritual experience.

4- Pranayama.
Yoga breathing exercises, also known as Pranayama, are an important part of a developing yoga practice. Pranayama is one of the Eight Limbs of Yoga, as defined by the Yoga Sutras of Patanjali. In addition to deepening your yoga practice,
learning ways to calm or invigorate the body through breathing will greatly benefit your life off the mat.Breathing is an involuntary act; it is an essential part of life.

5- Pratyahara (Control of the Senses).
Pratyahara means drawing back or retreat. The word ahara means "nourishment"; pratyahara translates as "to withdraw oneself from that which nourishes the senses.
" In yoga, the term pratyahara implies withdrawal of the senses from attachment to external objects.
It can then be seen as the practice of non-attachment to sensorial distractions as we constantly
return to the path of self realization and achievement of internal peace.
It means our senses stop living off the things that stimulate; the senses no longer depend on these stimulants and are not fed by them any more.

6-  Dharana (Concentration and cultivating inner perceptual awareness).
Concentration, meaning the ability to focus on something uninterrupted by external or internal distractions.

7- DHYANA.
Meditation. Building upon Dharana, the concentration is no longer focused on a single thing but is all encompassing.

8- Samadhi
Bliss. Building upon Dhyana, the transcendence of the self through meditation. The merging of the self with the universe.
Sometimes translated as enlightenment.

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