Etymology of the Korean currencies
The won is the currency of both North and South Korea. "Won" is a cognate of the Chinese currency unit, the yuan (//), and the Japanese currency unit, the yen (; ¥), meaning "round object". The won is subdivided into 100 jeon ().
Convertibility
Some countries pass laws restricting the legal exchange rates of their currencies or requiring permits to exchange more than a certain amount. Some currencies, such as the North Korean won, the Transnistrian ruble, and the Cuban national peso, are officially nonconvertible and can only be exchanged on the black market. If an official exchange rate is set, its value on the black market is often lower.