Florence Nightingale, known as the founder of modern nursing, played a pivotal role in transforming healthcare practices in the 19th century. Her work during the Crimean War revealed the necessity for sanitary conditions in hospitals, leading to a significant reduction in the death rate due to infections. Nightingale established training schools for nurses, emphasizing the importance of education, sanitation, and compassionate care. Her innovative use of statistics demonstrated the impact of hygiene on patient outcomes, and her writings helped to professionalize nursing as a respected field. Nightingale's legacy continues to influence nursing education and practice worldwide today.