Yam, niyam, asan, pranayam, pratyahar, dharana, dhyan samadhiya ashto angani.
The eight steps of Yoga are: yom, self-restraint; niyam, fixed observance; asan, posture; pranayam, breath regulation; pratyahar, abstraction; dharana, concentration; dhyan, contemplation; samadhi, trance.
The eight steps of yoga. This is the whole science of yoga in one sentence, in one seed. Many things are implied. First, let me tell you the exact meaning of each step. And remember, Patanjali calls them steps and limbs, both. They are both. Steps they are because one has to be followed by another, there is a sequence of growth. But they are not only steps: they are limbs of the body of yoga. They have an internal unity, an organic unity also, that is the meaning of limbs.
For example, my hands, my feet, my heart – they don’t function separately. They are not separate; they are an organic unity. If the heart stops, the hand will not move then. Everything is joined together. They are not just like steps on a ladder, because every rung on the ladder is separate. If one rung is broken the whole ladder is not broken. So Patanjali says they are steps, because they have a certain, sequential growth – but they are also angas. Limbs of a body, organic. You cannot drop any of them. Steps can be dropped; limbs cannot be dropped. You can jump two steps in one jump, you can drop one step, but limbs cannot be dropped; they are not mechanical parts. You cannot remove them. They make you. They belong to the whole; they are not separate. The whole functions through them as a harmonious unit.
So these eight limbs of yoga are both steps, steps in the sense that each follows the other, and they are in a deep relationship. The second cannot come before the first – the first has to be first and the second has to be second. And the eighth will come to be the eighth – it cannot be the fourth, it cannot be the first. So they are steps and they are an organic unity also.
Osho, Yoga: The Alpha and the Omega, Vol 5, Ch 5 (excerpt)