What was the code name of the first atomic bomb dropped on Hiroshima?

Little Boy was the code name of the first atomic bomb dropped on Hiroshima.

The United States dropped Little Boy on Hiroshima on August 6, 1945. It was a uranium-235 gun-type weapon carried by the B-29 bomber Enola Gay, commanded by Colonel Paul Tibbets. The bomb exploded at approximately 8:15 a.m. local time.

Little Boy was different from Fat Man, the plutonium implosion bomb dropped on Nagasaki on August 9. The two weapons used different designs and nuclear materials, even though both were developed through the wartime Manhattan Project.

The Hiroshima bombing was followed by the Soviet declaration of war on Japan and the invasion of Manchuria, then by the Nagasaki bombing. Japan announced its surrender on August 15, and the formal surrender document was signed on September 2. The bomb’s use remains central to historical debates about the end of the Pacific War.