Nursing theories are systematic frameworks that guide nursing practice, education, and research. They provide a foundation for understanding patient care and help nurses make informed decisions. These theories can focus on various aspects of nursing, such as patient relationships, health promotion, and the role of the nurse in the healthcare system. There are several well-known nursing theories, including those developed by Florence Nightingale, Jean Watson, and Dorothea Orem. Each theory offers unique perspectives on how to approach patient care and emphasizes different elements, such as the importance of the environment, caring, or self-care.