“tvastu sāṁye citta bhedāt tayor vibhakttaḥ panthāḥ"
 - Patanjali
The world of matter is entirely neutral and homogeneous. The differences like good/evil, beauty/ugliness are sheer perceptions oriented towards measly goals.

Kundalini refers to coiled serpent at the base of the spine. As Sigmond Freud said, sexual energy is the source of all energies in mankind, which is partially agreeable. The serpent of kundalini represents this coiled up energy, which is source of all the energies of mankind. 

When this energy is dormant at the perineum, the base of spine (mooladhara), survival becomes the primary concern of the individual. When it starts rising up to the sacral region (svadishthana), the person becomes a pleasure seeker. When it hits the navel region (manipura), he/she starts expressing, doing things either to accumulate wealth or seeking social uplift. When it raises to the heart region (anahata), he/she grows compassion. Throat region (vishuddhi) activates clarity and the flow of creativity. When it reaches the region between the eyebrows (ajna), the region of pituitary gland, it unravels the higher levels of consciousness and intuitiveness. Finally, the much harder to reach point, the crown of the head (sahasrara), one attains enlightenment, siddhahood, in common terms, the ultimate possibility of a mankind.
Kundalini Chakra Endocrine Gland Life Aspect
Muladhara Adrenal Glands Surivial Instinct
Svadishthana Testis/Ovaries Reproductivity and desires
Manipura Pancreas Digesion, Energy and Drive
Anahata Thymus Gland Temperature & Compassion
Vishuddhi Thyroid Gland Growth and Creativity
Ajna Pituitary Gland Master Switch for all glands
Sahasrara (Thuriyam) Pineal Gland Beyond our comprehension
Kundalini can be awakened;
by Pranayama, Asanas and Mudras - Hatha Yogis;
by concentration and training of the mind - Raja (Kriya) Yogis;
by devotion and perfect self surrender - Bhaktas;
by analytical contemplation and sheer will - Jnani (ஞானி) Yogis;
by Mantras - Tantrikas;
by the grace of the Guru (Guru Kripa) through touch, sight or mere sankalpa of a right Guru.

Rousing of kundalini and its union with siva at the sahasrara chakra is the state of samadhi and it leads towards one's mukti (liberation). State of samadhi is made possible only by awakening the kundalini.

As soon as it is awakened, it pierces the muladhara chakra (Bheda). It should be taken to sahasrara through various chakras. When kundalini is at one chakra, intense heat is felt there and when it leaves that centre for another chakra, the former chakra becomes very cold and appears lifeless. After kundalini reaches the ajna(ஆக்ஞை) charka region, prana passes upwards through brahma nadi. Hatha yogis take it up to sahasrara chakra through some special exercises such as mahabheda and sakti chalana. At this point, it is merely the mind power, determination and all the siddhis attained so far is needed to take it to sahasrara chakra.

When there is throbbing in muladhara, when hairs stand on their roots, when uddiyana, jalandhara and mulabandha come involuntarily, these are the indications that kundalini has awakened.

Need and the benefits of kundalini awakening for the yogi;
- You get vastly increased energy levels for daily living and to progress in the sadhana
- Your entire energy system grows and expands. You become able to process more psychic energy and abilities awaken.
- Our samskaras (karmic blocks/veils) get released fast. These issues are what’s blocking your psychic development, life and death cycle.

Awakening kundalini releases abundant energy. Body and mind needs to be prepared to handle such energies. Hence the 8-fold path of hatha-yoga is emphasized. The first four steps of yama, niyama, asana, pranayama is foundation to handle these energy bursts during the later stages of pratyahara, dharana, dyana, samadhi.