VJ Day, which stands for Victory over Japan Day, marks the end of World War II.
It is celebrated on the 15th of August, the date in 1945 when Japan announced its surrender to the Allied forces.
This effectively ended the Second World War, following the surrender of Germany on VE Day (May 8th).
The formal signing of the surrender documents occurred on September 2nd, 1945.
The two atomic bombs dropped on Japan killed thousands of civilians but prevented a full-scale invasion of the Japanese mainland, and other territories, which would have caused far more deaths to allied servicemen and probably prevented the murder of the thousands of prisoners of war held by the Japanese.