What's Yoga really about?

Hatha Yoga is not really about 'postures', it is about 'energy flow'.

"Commentators of ancient yogic texts such as the Hatha Yoga Pradipika have stated that union between ida, pingala and sushumna is hatha yoga."



"An important point that has been omitted by the commentators is that hatha yoga is not only the union of prana [life-force] and mind. In fact, it means the union of prana and mind with the Self.
Now, let us clarify this.
In the spine there are three major nadis known as ida, pingala and sushumna.
Nadi here does not mean nerve. It is not a physical channel.
Nadi means flow, like the flow of electricity within a cable.
One wire carries the 'negative' force and another carries the 'positive' force of electricity.
So in hatha yoga, ida nadi represents the negative force, the flow of consciousness, pingala represents the positive force, the flow of vital energy, and sushumna nadi represents the neutral force, the flow of spiritual energy.
The union, the connection between these three flows occurs in ajna chakra (the eyebrow centre).
Therefore let us revise the literal meaning of hatha yoga.
When this union takes place there is an instant awakening in mooladhara chakra at the base of the spine.
This is the seat of primal energy or kundalini shakti.
The awakening of kundalini shakti is the subject matter of hatha yoga.
Through the practices of hatha yoga, union is brought about.
As a result of that union, the awakening of kundalini takes place. When awakening occurs, then kundalini ascends to higher realms of consciousness, and finally it is established in sahasrara chakra at the crown of the head.
When kundalini is established in sahasrara chakra, that is called yoga, not hatha yoga.
This is the difference between yoga and hatha yoga.
Yoga means union of Shiva (consciousness) and Shakti (energy).
Shakti is kundalini energy; Shiva is the supreme consciousness seated in sahasrara chakra.
When awakening takes place in mooladhara chakra at the base of the spine, then kundalini starts ascending.
She ascends through sushumna, not through ida and pingala.
Sushumna is the highway for kundalini. It passes through various chakras, sometimes all of a sudden and sometimes very slowly. When it unites with ida and pingala in ajna chakra, that is called hatha yoga. Then after this first union, it forges ahead to sahasrara chakra. There it unites with the supreme consciousness, Shiva.
That is called yoga, which means the ultimate union.
Therefore the ultimate object of hatha yoga is to experience yoga."


Swami Muktibodhananda 
in the commentary of the Hatha Yoga Pradipika (one of the primary source texts on Hatha Yoga),
published by the Yoga Publications Trust, Bihar, India