Multiple Sclerosis - M S is an inflammatory disease in which the fatty myelin sheaths around the axons of the brain & spinal cord are damaged.
https://en.wikipedia.org/wiki/Multiple_sclerosis
Multiple Sclerosis: MedlinePlus - Multiple sclerosis (MS) is a nervous system disease that affects your brain and spinal cord.
https://medlineplus.gov/
National MS Society - An association pursuing prevention, treatment and cure of nervous system disease called multiple sclerosis (abbreviated MS).
https://www.nationalmssociety.org/