Florence Nightingale was a nurse who changed how hospitals were operated. When she was a nurse during the Crimean War, she saw how dirty the hospitals were. More soldiers were dying in the hospital than on the battlefield. She decided to change this by making sure hospitals were clean. In 1860, after the Crimean War was finished, she set up a nursing school at St. Thomas Hospital in London.
Later in her life, she became a writer, and wrote down what she discovered in plain English so that those who couldn’t read very well could understand what she discovered.