I've heard a lot about the eight limbs of Yoga. Could you explain more exactly what this involves?

Ans : The eight limbs of Raja Yoga are: yama, niyama, asana, pranyama, pratyahara, dharana, dhyana and samadhi. Out of these, the first four are the preliminary stages. The yoga proper starts from pratyahara, or abstraction of the mind and the senses. Yama is the cultivation of certain virtues. Niyama is the following of certain daily observances. Asana is the acquisition of perfect steadiness of pose and pranayama is the discipline, control and regulation of our gross physical breath, which is connected with the inner subtle nerve-currents. The purpose of the asanas in raja yoga is different from hatha yoga, in that the asana in raja yoga means holding any one steady pose for the purpose of meditation. Pratyahara is the withdrawal of our senses and mind from the external objects of this universe, and dharana is the fixing of the mind on the object of meditation. Dhyana is mastery over dharana and continuous, unbroken fixing of the mind on the object of meditation. Dharana is sporadic, but when you have attained mastery over it, you are able to fix your mind upon the object of meditation steadily for a long time. In the depths of meditation you transcend the lower, physical consciousness and you experience the highest super-consciousness. This is called samadhi.

Raja yoga helps us first to control the gross, physical body and then step-by-step it leads us on to the control of subtler sheaths; the pranic sheath, the mental sheath, the intellectual sheath, the bliss sheath, and it takes us to the eternal, ever-perfect Self, which is beyond all these sheaths. Thus the approach is made, starting from the most external, the physical body, to subtler and subtler bodies. Raja yoga is then a very scientific and logical method of inner purification and self-perfection.