Ryo served as a weight unit in the traditional East Asian system of weights and measures, and also served as a currency unit in Japan and in China; in Japan, the unit of gold coins in the early modern ages, and in China, the unit of hyoryo ginka (silver coin used as currency by weight).
両（りょう）は、尺貫法における質量の単位であり、また、近世の日本における金貨、および中国における秤量銀貨の通貨単位である。