Multiple sclerosis is an autoimmune disease of the central nervous system characterized by demyelination of nerve fibers. It most commonly presents in young adults between 20-40 years of age and is more prevalent in women. Symptoms vary depending on the location of lesions but commonly include weakness, numbness, vision issues, and balance problems. Diagnosis involves MRI of the brain showing characteristic white matter lesions. Treatment focuses on reducing relapses through disease-modifying drugs for relapsing-remitting MS, and managing symptoms like spasticity, pain, and bladder problems.