Chronic bronchitis and emphysema are the two most common conditions of COPD.

COPD develops slowly, and people are often not diagnosed with it until their 50s, when the disease has greatly affected their lung function.

The respiratory system includes the nose, pharynx, larynx, trachea, and lungs.

Your lungs are remarkable organs with multiple roles. Each day, up to 2,300 gallons of air pass through your lungs.

Chronic bronchitis is a long-term inflammation of the bronchi, which results in increased production of mucus.

Emphysema is a chronic lung condition in which the air sacs of the lungs are damaged or destroyed. This damage is irreversible.

You take an average of 16 breaths every minute. It's a reflex—you don't pay attention unless there's a problem. But a rising number of us literally can't catch our breath.

A short glossary of terms associated with chronic obstructive pulmonary disease.