The Discovery of Penicillin, an Accidental Miracle by Sir Alexander Fleming

One fine morning in 1928, Alexender Fleming returned to his lab to find mould growing on a Petri dish of Staphylococcus bacteria. He noticed that the mould was restricting the growth of the bacteria around it. He quickly discovered that the mould produced a self-defense chemical capable of killing bacteria. He named the substance Penicillin.