The project's bombs consisted of "Little Boy," "Fat Man" and "Trinity."
Little Boy
"Little Boy" was a uranium gun-type fission weapon. This was dropped on Hiroshima, Japan.
Fat Man
The Fat Man was an upgraded version of the "Little Boy": a plutonium implosive-type nuclear weapon. This was dropped on Nagasaki, Japan.
Trinity
"My first impression of the explosion was the very intense flash of light, and a sensation of heat on the parts of my body that were exposed. Although I did not look directly towards the object, I had the impression that suddenly the countryside became brighter than in full daylight."
-- Trinity Test, July 16, 1945 Eyewitness Report by Enrico Fermi