A stethoscope is a medical instrument used by healthcare professionals to listen to internal sounds of a patient's body, primarily the heart and lungs. It consists of a long tube connected to a chest piece, which has one or two microphones that amplify sounds. Stethoscopes are essential tools for diagnosing various conditions, as they help detect abnormal heartbeats, lung issues, and other health problems. Invented by René Laennec in the early 19th century, the stethoscope has evolved over time, with modern versions offering improved sound quality and comfort. There are different types of stethoscopes, including acoustic, electronic, and ultrasound models, each serving specific purposes in medical practice.