ABSTRACT: Smoking leads to disease and disability and harms nearly every organ of the body. Smoking causes cancer, heart disease, stroke, lung diseases, diabetes, and chronic obstructive pulmonary disease (COPD), which includes emphysema and chronic bronchitis. It increases risk for tuberculosis, certain eye diseases, and problems of the immune system, including rheumatoid arthritis. Secondhand smokers are also at great risk of developing certain disease conditions like stroke, lung cancer, and coronary heart disease in adults.