Nengō (年号) is a system of era names used in Japan to mark periods of time. Each nengō corresponds to the reign of an emperor, and a new nengō is typically established when a new emperor ascends the throne. This system helps to organize historical events and cultural developments within specific time frames. The current nengō is Reiwa, which began in 2019 with the ascension of Emperor Naruhito. Nengō is often used in official documents, calendars, and cultural references, reflecting Japan's unique approach to timekeeping and its deep historical traditions.