Here's why:

* Stratified squamous means the epithelium has multiple layers of cells, with the most superficial layer being flat (squamous).

* Keratinized means the cells in the superficial layers are filled with keratin, a tough protein that provides protection and waterproofing.

Thick skin, found on the palms of the hands and soles of the feet, requires this type of epithelium for its unique functions:

* Protection: The multiple layers and keratin provide a barrier against abrasion, water loss, and pathogens.

* Durability: The keratin makes the skin tough and resistant to wear and tear.

Thin skin, found on most of the body, has stratified squamous non-keratinized epithelium. This type still has multiple layers but lacks the same amount of keratin, making it thinner and more flexible.