Esophageal diverticulum is a condition characterized by the formation of pouch-like protrusions in the wall of the esophagus. These pouches can collect food and secretions, leading to difficulty swallowing, regurgitation, and other complications. Esophageal diverticula can be congenital or acquired and are classified into three types: Zenker's diverticulum, traction diverticulum, and epiphrenic diverticulum.