the manhattan project
research and development project that produced the first atomic bombs during World War II. It was led by the United States with the support of the United Kingdom and Canada. From 1942 to 1946, the project was under the direction of Major General Leslie Groves of the U.S. Army Corps of Engineers. The Army component of the project was designated the Manhattan District; "Manhattan" gradually superseded the official codename, Development of Substitute Materials, for the entire project.
- Developed three bombs in 1945 “Trinity”, “Little Boy” and “Fat Man” the trinity was used for testing
- there were two kinds of nuclear bombs uranium and plutonium bomb