Sclerosis is a medical condition characterized by the hardening or thickening of tissue in the body. This can occur in various organs and systems, leading to impaired function. One common type is multiple sclerosis, which affects the nervous system and disrupts communication between the brain and the body. Another form is systemic sclerosis, also known as scleroderma, which primarily affects the skin and connective tissues. In this condition, collagen builds up excessively, causing skin to become tight and hard. Sclerosis can vary in severity and may require different treatment approaches depending on the affected area.