Florence Nightingale's contributions to nursing are vast and transformative. She introduced a series of hygiene and sanitary reforms that significantly reduced mortality rates. Nightingale also emphasized the importance of a clean, well-ventilated environment for patient recovery. Her book, "Notes on Nursing: What It Is and What It Is Not," published in 1859, serves as a foundational text for nursing education. She also established the Nightingale Training School for Nurses in 1860, which professionalized nursing and laid the groundwork for modern nursing education.