who created the atomic bomb.why did they use it
The history of the atomic bomb began with the Manhattan Project. It was tasked to create the bomb beginning in 1939. The scientists who invented the bomb included Robert Oppenheimer, Edward Teller, Rudolf Peierls and many others.
In the years since the two atomic bombs were dropped on Japan, a number of historians have suggested that the weapons had a two-pronged objective. First, of course, was to bring the war with Japan to a speedy end and spare American lives.