This document outlines key concepts in nursing philosophy and theory. It begins by defining philosophy of nursing as beliefs about the nature and values of the nursing profession. Nursing theory is then discussed as organized bodies of knowledge that define nursing practice. Theories are categorized into grand, middle-range, and practice-level. Major concepts in theories like concepts, assumptions, and propositions are defined. The document also discusses the purposes of nursing theory in guiding practice and generating knowledge, and how nurses can apply theory in areas like organizing patient data, decision-making, and evaluating outcomes.