There are many people and discoveries that have contributed to our understanding of the atom and its parts. Our understanding of atomic structure has changed greatly over time as new contributions to the field refined our thinking. The powerpoint notes below contain most of the important people and major experiments which shaped our understanding. Pay special attention to the different models through time (Democritus’s Billiard Ball Model, Thomson’s Plum Pudding Model, Rutherford’s Model, Bohr’s Model, and the Quantum Model)
History of the Atom (PDF notes)