it begins in the 5th century B.C., with Democritus theory "matter consists of the indivisible, indestructible units that interact with each other" Moving onto 18th century when Dalton's proposed the atomic theory and then passing in the 20th century with the discovery of subatomic particles, plum pudding model, Rutherford model, Bohr model, and quantum theory, the journey was full of
discoveries and informative.