what was the manhattan project during world war 2?

In June 1942, the US Army established the Manhattan Project to handle its part in the atom bomb project and began the process of transferring responsibility from the Office of Scientific Research and Development to the military. In September, Groves was appointed director of what became known as the Manhattan Project. He selected Oppenheimer to head the project's secret weapons laboratory. This choice surprised many, because Oppenheimer had left-wing political views and no record as a leader of large projects. Groves was concerned by the fact that Oppenheimer did not have a Nobel Prize and might not have had the prestige to direct fellow scientists.But he was impressed by Oppenheimer's singular grasp of the practical aspects of designing and constructing an atomic bomb and by the breadth of his knowledge. As a military engineer, Groves knew that this would be vital in an interdisciplinary project that would involve not just physics, but chemistry, metallurgy, ordnance and engineering. Groves also detected in Oppenheimer something that many others did not, an "overweening ambition" that Groves reckoned would supply the drive necessary to push the project to a successful conclusion. Isidor Rabi considered the appointment "a real stroke of genius on the part of General Groves, who was not generally considered to be a genius".

The Manhattan Project was a research and development started by the US military during the second world war to produce the first nuclear weapons. Nuclear physicist Robert Oppenheimer was the director of the Los Alamos Laboratory that designed the actual bombs. Leslie Groves was initially not convinced that Oppenheimer could lead other scientists, but he was impressed that Oppenheimer had such a full grasp of the subject to lead this into an actual materialized atomic bomb. Because of the interdisciplinary nature of the subject, Oppenheimer also had an extreme drive to see the project to completion.