Actually, Patanjali, an ancient sage, defined yoga as the ‘restraining of thought waves'. He compiled ‘Patanjali's Yoga Sutras', the aphorisms of yoga, in which he provides an eight-limbed approach for the well-being and purification of body, mind and soul. This eight-limbed approach, known as Ashtanga Yoga, is not to be mistaken as a step-by-step approach but a multidimensional approach in which all eight limbs are practised simultaneously.
The 8 Limbs are
1) Yamas - the five social ethics
a) Ahimsa - Non-violence in action, speech and thoughts
b) Satyam - Truthfulness in intention, remaining established in the higher truth
c) Asteya - Non-stealing
d) Brahmacharya - Divine conduct, celibate when single, faithful when married
e) Aparigraha - Not accumulating things unnecessarily and not desiring things that belong to others.
2) Niyamas - the five personal ethics
a) Saucha - Cleanliness of the body and mind
b) Santosha - Contentment, remaining happy
c) Tapas - Austerity and self-discipline
d) Swadhyaya - Study of the Self, abiding in the Self
e) Ishwarapranidhana - Surrendering to God, honouring the Divine.
Yamas and its complement, Niyamas, represent a series of ‘right living’ or ethical rules.
3) Asanas - Yoga postures or postures.
4) Pranayamas - Proper regulation of life force (Prana) through certain breathing techniques.
5) Pratayahara - Taking the senses inwards.
6) Dharana - One-pointed focus.
7) Dhyana – Meditation.
8) Samadhi - the highest state of consciousness. This is possible to achieve during Meditation
Gurudev Sri Sri Ravi Shankarji