This document discusses asthma, including its aetiology, or causes, which can be genetic factors, viral infections, smoking, or environmental triggers like upper respiratory infections, allergies, food, exercise, or psychological factors. It also examines the clinical features of asthma like respiratory distress, cyanosis, wheezing, and expiration taking longer than inspiration. Diagnosis involves physical examination, pulmonary function tests, chest x-rays, and checking serum IgE levels. Differential diagnoses that should be considered include laryngeal edema, congestive heart failure, COPD, and eosinophilic pneumonias.