This document defines COPD and provides details about its symptoms, causes, diagnosis, and treatment. COPD is a progressive lung disease characterized by difficulty breathing caused by damage to the lungs. The most important risk factor is cigarette smoking. Symptoms include a chronic cough, sputum production, and shortness of breath. Diagnosis involves pulmonary function tests showing obstruction and reduced airflow. Treatment focuses on smoking cessation and includes bronchodilators, steroids, oxygen therapy, antibiotics for exacerbations, and surgery in severe cases.