what is kundalini yaga in yoga?

Answer 1

Well, it is kundalini Yoga and not yaga. An yaga is a sort of yajna (offerings into fire with chanting of mantras). There are Raja Yoga, Hatha Yoga and Kundalini Yoga etc. In kundalini yoga, the yogi raises the kundalini energy lying coiled and dormant at the root of the spine (mooladhara chakra), through the other chakras to sahasra. In this process, the three nadis, ida, pingala and sushumna get activated.

I think you will find good books on kundalini yoga and I would suggest that you read them. One thing is that it is rather dangerous to do this yoga on your own without the supervision of a competent guru.