Raynaud's Phenomenon is a condition that affects blood flow to certain parts of the body, usually the fingers and toes. It occurs when small blood vessels constrict excessively in response to cold temperatures or stress, leading to color changes, numbness, and pain in the affected areas. The skin may turn white or blue before returning to a normal color as blood flow resumes. This phenomenon can be classified as either primary or secondary. Primary Raynaud's occurs on its own without any underlying health issues, while secondary Raynaud's is associated with other medical conditions, such as scleroderma or lupus. Treatment often focuses on lifestyle changes and managing symptoms.