Gengō (元号) is a Japanese era name system used to mark periods in history. Each gengō is associated with the reign of an emperor, and it typically changes when a new emperor ascends to the throne. The current gengō, Reiwa, began in 2019 with the ascension of Emperor Naruhito. The use of gengō dates back to the 7th century and serves as a way to organize historical events and documents. Each era name is chosen for its auspicious meaning, reflecting the hopes for the period. Gengō is still used today in official documents, calendars, and cultural references.