Rare, deadly, and often missed, some skin cancers develop in areas that rarely see the sun. Scientists are still learning about them, but here's what we know.

Asthma (reactive airway disease) affects an estimated 34 million people in the U.S. Find in-depth asthma information, including treatments, triggers, and prevention.

High blood pressure affects I in 4 American adults. Find in-depth high blood pressure and hypertension information including its causes, symptoms, and treatments.

WebMD's COPD Health Center provides in-depth information on chronic obstructive pulmonary disease including symptoms, causes, treatment options, diagnosis, and tests.

Your sleep position can make you more likely to snore, have back pain, or get a good night’s rest. Find out what effects your sleep position may have on your health.