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.
When did the Korean War Start and End. For many years, the Japanese had occupied Korea. At the end of the Second World War, Soviet and US forces entered Korea and fought the Japanese. Japanese forces surrendered on September 9, 1945. The soviets and the US decided that Korea should be split into two halves (North Korea and South Korea). The Koreans, however, wanted to unite into one country. North Korea decided force must be used to unite the two countries.