Tuberculosis is an infection caused by the Mycobacterium tuberculosis bacteria, which most commonly affects the lungs but can infect other parts of the body. Symptoms include cough, sputum, blood, night sweats, chest pain, weight loss and fever. TB is a communicable disease spread through the air via sneezes or coughs. India has a high burden of TB cases, accounting for one fourth of global annual incidence. TB is diagnosed through tests like sputum smear, blood tests, chest x-rays and the Mantoux test. Prevention methods include avoiding close contact with active TB patients, using face masks, vaccination with BCG, and following treatment instructions.