Meningitis is an inflammation of the meninges, often caused by viral or bacterial infections, and can also arise from non-infectious factors such as cancer or injury. Common symptoms include fever, headaches, and neck stiffness, with diagnosis typically involving a physical exam and lumbar puncture. Treatment varies by age group and type of meningitis, including antibiotic therapy for bacterial cases, while non-pharmacological methods such as rest and hydration may support recovery.