Dorothea Orem was an American nurse theorist born in 1914 who developed the Self-Care Deficit Nursing Theory. She received her nursing degree and later pursued further education, earning several honors for her work. Orem's major theory centered around the idea that nursing is needed when individuals cannot care for themselves. It included the concepts of self-care, self-care deficits, and nursing systems. The theory aims to help nurses assess patient needs, design care plans, and evaluate outcomes of nursing interventions. Orem's work has greatly influenced nursing practice and education.