Community-acquired pneumonia (CAP) is an acute lung infection outside hospitals, significantly affecting millions annually in the U.S., requiring hospitalization for a quarter of cases. The document details the epidemiology, causative organisms, diagnosis methods, treatment guidelines, and management strategies, including the need for antibiotics, risk stratification for hospitalization, and criteria for ICU admission. Recommendations include using severity-of-illness scores for treatment decisions, monitoring response to therapy, and addressing potential complications based on patient presentations.