The concept of nursing has changed from the past to present.These changes are mainly due to change in the concept of health patterns of illness and diseases, and also the progress made in science and technology.In the past,people used to think of nursing only within the four walls of hospitals,where the role is limited to caring for sick and assisting the doctors in treatment.

Now the concept of nursing has expanded from hospital to community with emphasis on preventive and promotional aspect of health care;the role of the nurse is more expanded towards the promotion of health and prevention of diseases rather than just providing care to the sick in the hospital.