Ida and Pingala
Ida is a nerve channel on the left side of the sushumna in which the vital air passes through. Also the left nostril. The ida corresponds to the tamasic quality of nature. ("Cool, white, lunar, Moon-flow".)
Pingala - (lit.‘yellow’, "sunlike", also solar, red.) A nerve channel on the right side of the sushumna in which the vital air passes through. Also the right nostril. It corresponds to the rajasic quality of nature.