Oil is an essential lubricant in your engine. It lets metal press against metal without damage. For example, it lubricates the pistons as they move up and down in the cylinders.
1 By the time of the Japanese surrender in August 1945, Korea was the second-most industrialized nation in Asia after Japan itself.  But the wartime mobilization of 1937-45 had reintroduced harsh measures to Japanese colonial rule, as Koreans were forced to work in Japanese factories and were sent as soldiers to the front.
The History Of The South Korean Won. The Korean peninsula is known to have been inhabited since 4,000 BC. The use of currency in Korea dates to at least third-century B.C. in the Yan and Gojoseon kingdoms, where Asian knife coins, a type of metallic token in the form of weapons and farm implements, were traded.