The unit of currency used in Japan is the yen (JPY). The yen is one of the most traded currencies in the world and is symbolized by the sign "¥." It was first introduced in 1871, replacing the complex monetary system that existed before, as part of the Meiji Restoration's efforts to modernize Japan's economy. The Bank of Japan issues yen notes and coins, which come in various denominations. The yen plays a critical role in international finance and trade, and its value can be influenced by economic factors, monetary policy, and global market trends. Understanding the yen is essential for anyone engaging with Japan economically or as a traveler.