The full form of COPD is Chronic Obstructive Pulmonary Disease. Breathing becomes challenging due to a lung illness that advances. Damage to the lung tissue and persistent inflammation of the airways are characteristics of COPD. The two main types of COPD are emphysema and chronic bronchitis.

1. Chronic Bronchitis: This illness is characterised by bronchial tube (the airways that deliver air to the lungs) irritation that lasts a long time. It causes a chronic cough and an increase in mucus production.

2. Emphysema: This condition diminishes the lungs' capacity to expand and contract due to the breakdown of the alveoli, the air sacs in the lungs. As a result, the lungs become less flexible.

Common signs of COPD include wheezing, shortness of breath, persistent cough, and excessive mucus production.