Alexander Fleming and his discovery of penicillin was a revolutionary step forward for humankind. This discovery put an end to the unnecessary death of millions attributed to post-surgery infections. He started off his career as a bacteriologist and discovered Lysozomes, present in bodily fluids and have antibacterial effects. Then serving in WWI at a field hospital and seeing first-hand the pain and death of such operations. He was later awarded a Nobel Prize and served as a personal physician to Winston Churchill. Penicillin was mass-produced after the attack on Pearl Harbor during WWII and has saved the lives of thousands of soldiers and civilians since.