Meningitis is an inflammation of the protective membranes covering the brain and spinal cord known as meninges. There are several types depending on cause and duration including bacterial, viral, fungal, parasitic, and tuberculous meningitis. Bacterial meningitis presents with fever, headache, and neck stiffness but may not show the classic triad. Diagnosis involves CSF study, MRI/CT, and culture. Treatment depends on identified pathogen but commonly includes IV antibiotics and steroids. Chronic meningitis can be caused by infection, malignancy, autoimmune disease or chemicals and presents with persistent headache and neurological deficits.