Lens hoods are primarily intended to prevent unwanted stray light from entering the lens and causing flare. They also provide a degree of protection for the lens from accidental impact and from the elements.
Nikon official product
Designed to protect the 1 NIKKOR 6.7-13mm f/3.5-5.6 VR lens
An Optional accessory bayonet type black Lens hood that attaches to select 1 NIKKOR lenses to protect the lens from flare when shooting