Vitiligo: This is a condition where patches of skin lose their pigment and turn white. It's relatively common and can be caused by autoimmune diseases, stress, or genetic factors. The appearance of well-defined white spots, especially on the face, hands, or areas around body orifices, is a hallmark of vitiligo.

Pityriasis Versicolor: A fungal infection caused by Malassezia yeast, leading to patches of skin that are lighter or darker than the surrounding areas. It's common in young adults and is associated with oily skin.
Eczema (Atopic Dermatitis): While eczema typically presents with red, itchy patches, some forms can lead to the appearance of white spots due to chronic scratching or as part of the healing process.
Idiopathic Guttate Hypomelanosis: A benign condition characterized by small, discrete, hypopigmented spots, often on the arms and legs, more common in older adults and those with a history of sun exposure.

Leprosy (Hansen's Disease): A chronic bacterial infection that can cause light-colored patches on the skin, among other symptoms. It's crucial to diagnose early to prevent nerve damage and disability.
Tuberous Sclerosis: A genetic disorder that can cause white spots (ash-leaf spots) on the skin, along with other systemic manifestations. Early diagnosis is critical for managing the condition and its complications.
Sarcoidosis: An autoimmune disease that can manifest with skin lesions, including hypopigmented patches, along with systemic symptoms. It requires prompt diagnosis to manage potential organ involvement.

Piebaldism: A rare genetic condition characterized by the absence of melanocytes in affected areas of skin and hair, leading to white patches and often hair loss.
Waardenburg Syndrome: A genetic disorder that affects the development of melanocytes, leading to patches of depigmentation, among other features like hearing loss and eye abnormalities.
Nevus Depigmentosus: A rare congenital condition where there is a localized loss of skin pigment, resulting in a single patch of hypopigmentation.