Primitive times saw illness attributed to spirits and demons, treated by witch doctors using herbs. Ancient Egyptians kept health records and used medicine, splinting fractures and bloodletting. Ancient Chinese used acupuncture and stone tools to treat disease. Greeks like Hippocrates established ethics for medicine through the Hippocratic Oath, while Aristotle dissected animals. Romans organized hospitals and Galen discovered anatomy through dissection of animals. The Dark Ages saw a decline until Renaissance where medical schools and anatomy study revived medicine. Major discoveries and pioneers then improved hygiene, vaccines, antibiotics, imaging, and more over centuries.