Trepanation, also known as trepanning or burr holing, is an ancient surgical practice involving drilling a hole in the skull to expose the brain. Dating back 7000 years, it was a risky procedure with low survival rates, but it played a crucial role in ancient cultures' medical treatments. Theories suggest it served as a tribalistic ritual or treatment for ailments like epilepsy. Trepanning's historic evidence spans the Neolithic era, and tools varied from stone knives to more complex instruments. While it fell out of use in Medieval Europe, modern medicine has refined and reintroduced trepanation for specific conditions.