The nurse has a key role in delivering health care services because nursing is concerned with the promotion of health, prevention of illness, care of the sick and injured, rehabilitation, and support of individuals and families. Nurses are in close and continuous contact with patients and therefore occupy a central position in the health-care team. They provide direct patient care, observe changes in health status, administer treatment, educate patients, provide emotional support, maintain a safe environment, and coordinate services provided by other health professionals. One of the most important roles of a nurse is to provide comprehensive patient care. The nurse assesses the physical, psychological, social and spiritual needs of the patient and plans appropriate nursing care. For example, a nurse caring for a patient with pneumonia monitors temperature, pulse, respiration and oxygen saturation, observes breathing difficulty, administers prescribed medicines and oxygen, encourages adequate fluids and rest, and reports deterioration to the doctor. Thus, nursing care contributes directly to recovery and prevention of complications. Nurses play an essential role in health assessment. They collect information about the patient's medical history, present complaints, physical condition, nutritional status, mental status and functional abilities. Regular assessment helps in early identification of health problems. For example, if a nurse notices that a hospitalized patient has suddenly developed difficulty in breathing, low oxygen saturation and increased respiratory rate, the nurse can immediately inform the medical team and initiate appropriate emergency measures. Early recognition may prevent a serious complication. Another important responsibility is administration of medicines and treatments. Nurses administer oral, injectable, intravenous and topical medications according to prescriptions and established safety principles. They verify the right patient, right medicine, right dose, right route, right time and appropriate documentation. They also observe therapeutic effects and adverse reactions. For example, while administering insulin to a diabetic patient, the nurse checks the prescribed dose, monitors blood glucose and observes for signs of hypoglycaemia. This makes medication administration an important component of safe health care. Nurses also have a major role in preventing infection. They follow standard precautions, hand hygiene, use of personal protective equipment, proper disposal of biomedical waste, aseptic techniques and appropriate cleaning procedures. For example, a nurse performing wound dressing uses sterile equipment and