I see you read the title... Trust me, this is not really a recipe for the development of W.M.D.'s, but I think some people may find it interesting to know how an Atom bomb functions.

First off, atoms (meaning unbreakable in latin) are the smallest fundamental unit that makes the physical environment around us. Certain types of atoms can release a tremendous amount of energy by being split through nuclear fission. Common media for this is Uranium or Plutonium.

Atoms usually consist of three common sub-atomic particles. Protons, neutrons, and electrons. If a radioactive material such as enriched Uranium is bombarded with neutrons, the atom will split, releasing more neutrons which split other adjacent Uranium. This is called an Atomic Chain Reaction. In an atomic bomb, the material being used for atomic fusion lets out a rapid reaction, which results in vast amounts of atomic energy. The only time nuclear bombs were ever used in war was when Hiroshima and Nagasake were bombed to end the Pacific War in WWII. Nuclear power plants are stationed all around the world today, and are a key part in providing energy to us.

By the way, Oppenheimer was the father of the Atom bomb, not Einstein. Einstein didn't even believe that the bomb could be used efficiently or strategically. However, Einstein is the father of relativity and his theories revolutionized modern day physics and life.