Systemic Sclerosis (SSc), commonly known as Scleroderma, is a rare, chronic, multisystem autoimmune connective tissue disease characterised by three defining pathological processes: immune dysregulation and autoantibody production, widespread vasculopathy (especially Raynaud's phenomenon), and progressive fibrosis of the skin and visceral organs. The hallmark is thickening and hardening of the skin due to excessive collagen deposition by activated fibroblasts. SSc is classified into two major subtypes — diffuse and limited — based on the extent of skin involvement, which guides prognosis and risk of internal organ complications. It carries the highest mortality of any systemic autoimmune rheumatic disease.