This document provides a guide to auscultation of breath sounds, a crucial diagnostic technique in respiratory assessment. It details the proper technique, including equipment, patient positioning, and the systematic approach to examining both anterior and posterior lung fields. The guide then meticulously explains the characteristics of normal and abnormal breath sounds, categorizing adventitious sounds (e.g., wheezes, crackles, rhonchi) by their acoustic properties and associated pathologies. Finally, it describes the use of vocal resonance tests (bronchophony, whispered pectoriloquy, egophony) to further evaluate suspected lung abnormalities.