First of all, 'chakra' in Sanskrit means 'wheel'. It refers to any circular spinning object in general. Shivananda informs us that there are innumerable chakras, but there are 7 major chakras and these are the most significant of all chakras because Kundalini shakti (energy) flows through them. The bodies of all living entities contain chakras, but the alignment of their chakras can and does differ based on their form. For example, our 7 major chakras are vertically aligned along our spinal column but the 7 major chakras for a dog (or any other quadruped for that matter) will be horizontally aligned because they walk on four legs. Kundalini shakti is envisioned as a female serpent, but this is only a symbolic representation. Shakti or energy is always considered to be feminine whilst the wielding of energy is always considered to be masculine. But really, what seems to be two are actually one, as energy could not exist if it could not be wielded and there could be no wielding or controlling if there were no energy. The universal feminine principle (Shakti) and the universal masculine principle (Shiva) are both eternal and entirely equal to each other, entirely complimentary to each other and entirely interdependent on each other. They are symbolically represented respectively as wife and husband in eternal marriage. Because shakti is inherently feminine, different manifestations of shakti are often personified as goddesses or simply as beings of female gender. Because kundalini shakti lies dormant in three and a half coils at the muladhar chakra (corresponding to the sacrum bone of the physical body) for most people, it is represented as a female serpent. There are many lesser-known chakras lying below and above the 7 major chakras (but none above the sahasra chakra, which lies on top of one's head). These chakras are subsidiary to the 7 major chakras. One of these lesser-known chakras is the hrit chakra which lies just below the anahata chakra. Another one of these lesser-known chakras is the guru chakra, lying slightly above the ajna chakra. There are two main lines of yoga - dhyana yoga (where meditation is the main discipline) and kundalini yoga - and there is a marked difference between the two. The first class of yoga is that in which samadhi (non-dual state of super-consciousness) is obtained by intellectual processes of meditation and the like, possibly with the aid of auxiliary processes of mantra, hatha yoga (other than the arousal of Kundalini) and by detachment from the world; the second stands apart as that portion of hatha yoga in which, though intellectual processes are not neglected, the creative and sustaining shakti of the whole body is actually united with Supreme Consciousness. The two main lines of yoga differ in both method and result. Yoga, in and of itself, is pure science, a complete science throughout. Its methods are precise and without ambiguity, yet the results obtained are experiential and therefore no two people can and do share exactly the same resultant experience. Hence, yoga is a subjective science and cannot be properly scrutinised by standard empirical means. This is not intended to be a 'convenient' statement in any way whatsoever. All altered states of consciousness obtained through sincere and intense practice of yoga are INTERNALLY (as opposed to externally) generated. Before one studies kundalini yoga, knowledge of the nadis (ida, pingala and sushumna in particular), chakras and kundalini itself is absolutely essential. Nadis Nadis are astral tubes, made up of astral matter (which is less dense and hence more fine than physical matter), that carry pranic currents. They can be seen by astral sight only. They are not nerves as they are commonly believed to be, but tubes of extreme fineness that carry currents of subtle electricity. They arise from the kanda, which is the size and shape of a bird's egg and lies above the genital organ and below the navel. In the body of a human being, the total number of nadis is 72,000. Of these, the ten most significant ones are called ida, pingala, sushumna, gandhari, hastajihva, pusha, yasasvini, alambusha, kuhu and sankhini. Of those ten, the chief nadi is sushumna followed equally by ida and pingala. Ida is the leftmost channel; pingala the rightmost channel and sushumna the central channel. Ida is of a white colour, feminine, cool in temperature, is represented by the Moon (ie. lunar energy, not specifically of 'our' Moon but referring to a universal principle), is associated with the cosmic river Ganga, originates in the muladhar chakra and terminates up in the left nostril. Pingala is of a red colour, masculine, hot in temperature, is represented by the Sun (ie. solar energy, not specifically of 'our' Sun but referring to a universal principle), is associated with the cosmic river Yamuna, originates in the muladhar chakra and terminates up in the right nostril. Ida cools the body, pingala heats it up. Sushumna is the psychic nerve lodged in the hollow of the spinal column (brahma-danda). It is reckoned as the sustainer of our universe, the path of our universe and the path to salvation itself. Situated at the back of the anus, it is attached to the spinal column and extends to the brahmarandhra (the subtle hole through which kundalini bursts out of) of the head and is invisible and subtle. It runs along the length of the spinal column. The real work of a kundalini yogi begins when sushumna begins to function. The chakras are located in the astral body and are therefore not perceptible to our gross senses. Even if they were perceptible in the physical body which they help to organise, they disappear with the disintegration of the organism at physical death (but of course remain a part of the organism's astral body). As far as the 7 major chakras or energy vortices are concerned, they are often called padmas (lotuses) in Sanskrit. This is because each chakra has a particular number of 'petals' with a luminous letter of the Sanskrit alphabet shining on each petal. The vibration of sound produced at each petal is represented by a corresponding Sanskrit letter. The letters exist in the petals in a latent form and can be manifested, and the vibrations of the nadis felt, during intense concentration. That chakras are likened to lotuses with petals is not a poetic description by any means. Throughout the ages, yogis absorbed in super-consciousness have described the chakras which they were able to see and perceive as having an appearance similar to that of a lotus with the nadis as its petals. The muladhar, svadisthan, manipur, anahata, vishuddha and ajna chakras have 4, 6, 10, 12, 16 and 2 petals respectively. Thus all the 50 letters of the Sanskrit alphabet are on the 50 petals. At every chakra a particular element preponderates and there is a presiding deity and shakti (personified as a goddess). There is also a certain geometric figure, a certain colour, a certain bija (seed) mantra, a certain animal and a certain level of consciousness in the astral plane associated with each chakra. The animal denotes that the chakra in question has the particular qualities of that animal. I will now proceed to describe these chakra associations in greater detail: Muladhar Chakra Muladhar chakra is located at the base of the spinal column. It lies between the origin of the reproductory organ and the anus. This is the support, as all other chakras are above this one. The sacral plexus tentatively corresponds to this chakra. This chakra is where Brahma-Granthi (the knot of Brahma) is located. From this chakra, four important nadis emanate, giving the appearance of petals of a lotus. The subtle vibrations made by each nadi are represented by the Sanskrit letters: vam, sam, sham and sam (pronounced somewhat differently). This chakra is associated with the earth element (solid matter). The yellow square in the chakra is the corresponding symbol for the earth element. The bija mantra is 'lam' and the associated animal is the elephant called Airavata. Muladhar chakra is sovereign over the bones, flesh, skin and hairs of the body. Patience is its positive attribute and greed is its negative attribute. Self-survival is its desire. Collecting and saving is its activity. The four petals of this chakra represents the four cardinal directions (ie. south, west, east and north). Repetition of the bija mantra 'lam' removes insecurities associated with this chakra. Each chakra has a manifestation of the Shiva (male) and Shakti (female) deities. The male deity of muladhar chakra is Brahma, who brings peace of mind and calms one's fears. The female deity is Dakini Shakti, who bestows protection from danger. As already mentioned, the associated animal of this chakra is the Airavata elephant. The Airavata elephant searches for food and follows orders. It has 7 trunks representing the 7 different colours of the rainbow and the 7 functions of sight, hearing, smell, taste, touch, defecation and sex.