Nursing is a profession within the health care sector focused on the care of individuals, families, and communities so they may attain, maintain, or recover optimal health and quality of life.Nurses may be differentiated from other health care providers by their approach to patient care, training, and scope of practice. Nurses practice in a wide diversity of practice areas with a different scope of practice and level of prescriber authority in each. Many nurses provide care within the ordering scope of physicians, and this traditional role has come to shape the historic public image of nurses as care providers. However, nurses are permitted by most jurisdictions to practice independently in a variety of settings depending on training level. In the postwar period, nurse education has undergone a process of diversification towards advanced and specialized credentials, and many of the traditional regulations and provider roles are changing.Nurses develop a plan of care, working collaboratively with physicians, therapists, the patient, the patient's family and other team members, that focuses on treating illness to improve quality of life. In the U.S. (and increasingly the United Kingdom), advanced practice nurses, such as clinical nurse specialists and nurse practitioners, diagnose health problems and prescribe medications and other therapies, depending on individual state regulations. Nurses may help coordinate the patient care performed by other members of an interdisciplinary health care team such as therapists, medical practitioners and dietitians. Nurses provide care both interdependently, for example, with physicians, and independently as nursing professionals.The American Nurses Association (ANA) defines nursing: