KUNDALINI might be interpreted both physically and metaphysically. The root KUNDA means "basin" or "source". From this point of view, kundalini means the mixture of primordial elements of earth. From a worldly, mundane point of view KUNDALINI appears regularly and produces real disasters once in a while as earthquakes and eruptions of volcanoes.
As far as "individual" kundalini is concerned, it is situated in the sexual region and represents a sort of "inner, hidden fire" with a huge potential. This KUNDALINI SHAKTI is, in fact, the sexual force itself that may enslave or free you from the human limited condition.
As a latent power, necessary to spiritual progress, kundalini shows especially to those who attempt to understand the mysteries of sexuality.
Tantra presents different methods of "waking up" and driving the kundalini energy. According to Gheranda Samhita, "The Great Goddess Kundalini, who is the primordial energy of the Self itself, sleeps in the region of sex. It has the shape of a snake coiled three and a half times.