The prime purpose of this article is to know about lung disease. Lung diseases are several of the most general medical circumstances in the world. Tens of millions of people suffer from lung disease in the U.S. Smoking, infections, and genetics are responsible for most lung diseases. The lungs are part of a complex apparatus, expanding and relaxing thousands of times each day to bring in oxygen and expel carbon dioxide. Lung disease can result from troubles in any part of this system.