Pneumonia is an inflammatory condition of the lung which affects primarily the small air sacs known as alveoli. Pneumonia is usually caused by virus’s infection, bacterial infection and in some cases by other microorganisms, auto immune diseases and medications. Bacterial pneumonia is caused by streptococcus pneumoniae. Mycoplasma pneumoniae, haemophilus influenzae, Legionella pneumophila are the other causes of bacterial pneumonia. Viral pneumonia is caused by pneumonia influenza, respiratory syncytial virus, and rhinovirus. Fungal pneumonia is due to fungi from soil or bird droppings. Pneumocystis jirovecii, crptococcus species, histoplasmosis species are the causative agents of fungal pneumonia. Symptoms include dry cough, fever, chest pain, and difficulty in breathing. Risk factors include smoking, cough, asthma, diabetes, heart failure, cystic fibrosis, chronic obstructive pulmonary disease, sickle cell disease, heart failure. The disease is diagnosis by blood test for the signs of bacterial infection, chest X ray to find the spread of infection, sputum test for the cause of infection, pulse oximetry to measure the level of oxygen in the blood. Antibiotics such as cephazolin, azithromycin and amoxicillin are recommended as the first line drug for community acquired pneumonia. Neuraminidase inhibitors are used in the treatment of viral pneumonia.