The pectoralis minor is a thin, triangular muscle located beneath the larger pectoralis major in the chest. It originates from the third to fifth ribs and attaches to the coracoid process of the scapula. This muscle plays a key role in stabilizing the shoulder and assisting in movements such as pulling the shoulder blade forward and downward. In addition to its role in shoulder movement, the pectoralis minor is involved in respiration. It helps elevate the ribs during deep inhalation, contributing to lung expansion. Understanding this muscle is important for those studying anatomy, physical therapy, and sports medicine.