Lung diseases refer to a variety of conditions that affect the lungs and respiratory system, making it difficult to breathe. Common types include asthma, chronic obstructive pulmonary disease (COPD), and pneumonia. These diseases can result from factors like smoking, pollution, or infections, leading to symptoms such as coughing, wheezing, and shortness of breath. Diagnosis of lung diseases often involves medical history, physical exams, and tests like chest X-rays or pulmonary function tests. Treatment options vary depending on the specific condition and may include medications, lifestyle changes, or therapies to improve lung function and overall health.