Skull wiki:
l, or cranium, is a bony structure of Craniates which serves as the general framework for a head. The skull supports the structures of the face and protects the brain against injury.
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Helmet wiki:
>For information about the band Helmet, see Helmet (band) A helmet (a 15th century loan from Middle French, a diminutive of Frankish helm, from Proto-Germanic *khelmaz, PIE *kelmo- "a cover") is a form of protective clothing worn on the head and usually made of metal or some other hard substance, typically for protection of the head from falling objects or high-speed collisions.
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