Nadis are pathways of pranic, spiritual and mental currents. They provide energy to the whole body. They are not physical or measurable, they are the channels of energy in the body. Out of thousands of energy channels or nadis seventy-two are considered important. The three major nadis are ida, pingala and sushumna. These nadis are located in the spinal column and passess through every chakra. The nadis emanate from mooladhara chakra. Ida, pingala and sushumna originate here. Emanating from the left side of the mooladhara chakra and passing through the intervening chakras in turn in a curving, criss crossing path, finally ending up on the left side of the ajna chakra, is the ida nadi. Emerging from the right side of the mooladhara chakra and passing in similar but opposite sense to that of the ida nadi, up to the right of the ajna is the pingala nadi. The sushumna nadi flows up through the middle. Ida and pingala indicate the realm of time. The ida and pingala nadis are the pathways of the two different aspects of prana. They represent the two opposite poles of the same energy. The ida is denoted as being negative and is also known as the chandra(moon) nadi. The pingala, on the other hand, is positive and is often called the surya(sun) nadi. These two nadis are associated with the two nostrils: pingala with the right and ida with the left. Sushumna is the passage where the kundalini rises. When the flow of breath is strong in the left nostril it indicates that ida is dominant, if the flow of breath is dominant in the right nostril it indicates pingala is dominant. When both ida and pingala is balanced the channel sushumna becomes active. When sushumna is active breath flows through both the nostrils simultaneously.