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 ().
Korean currency
The country then had to switch over to a new currency unit named "hwan" replacing won at 1 hwan = 100 won. Like South Korean won, this currency unit was also issued in banknotes initially but in 1959, coins denominated in hwan were also issued and were the first circulating coins in South Korea. Hwan had a peg with US dollar but with time it also got devaluated. This was the reason for the reintroduction of won in 1962 as the official currency unit. South Korean currency was still pegged to the US dollar until in 1997 when it was floated into the world market.