The Full form of DNS is Deviated Nasal Septum. DNS is a physical disorder of the nose, involving a displacement of the nasal septum. Some displacement is common, affecting 80% of people, mostly without their knowledge. Deviated nasal septum is defined as the deviation of nasal septum from center of the nasal cavity. The nasal septum consists of cartilage and bone which divides the nasal cavity into two equal halves. This deviation makes breathing difficult for a person because one of their nostrils is smaller than the other. DNS may be present either develop during growth or from birth, or may be caused by an injury to the nose or face. Conditions such as blockage of the respiratory tract, common cold etc. might be seen in the patient. Most of these deformities may not come to notice or create any symptoms. However, DNS may cause symptoms such as: nose bleeding, nose obstruction, snoring, preference for sleeping on a particular side, facial pain, postnasal drip and headache and sleep apnea. In order to prevent the occurrence of this disease, one should take care of injuries, use of protective equipment, wearing a helmet or seat belts etc.