Pneumonia is an inflammatory process in the lungs caused by infectious agents. It can be bacterial, viral, fungal or chemical. Symptoms include shaking chills, chest pain, cough with sputum, and shortness of breath. Diagnosis involves physical exam, chest x-ray, and sputum culture. Treatment is with antibiotics, oxygen therapy, and chest physiotherapy. Nursing care focuses on airway maintenance, sputum collection, chest physiotherapy, diet, infection control, and monitoring for complications like respiratory failure. With treatment, most patients improve within 2 weeks but elderly or very sick patients may need longer treatment.