Asthma is classified as a chronic lung condition that narrows and inflames the airways. The disease causes wheezing when you breathe, shortness of breath, coughing and chest tightness. The coughing normally occurs early in the morning or at night. Asthma affects people from all walks of life including children, men, and women but most often begin to experience it during childhood. In the U.S., over 25 million people suffer from asthma and 7 million of these are children. In order to understand the prevalence of asthma, it is important to know how the airways function. Airways are tubes that transport air into and out of the lungs. Victims of asthma are characterized by having inflamed airways. This inflammation makes the airways become swollen and very sensitive, and it also makes them react very strongly to different inhaled elements.