Nikon SLR Cameras

What would this extra part for my nikon d3100 do?

Alexis
Alexis

Http://www.amazon.com/52MM-TULIP-FLOWER-DIGITAL-CAMERAS/dp/B001UDJVAQ/

what is this for? And how do i put it on?
(i got it when i bought my camera it came free)

Hondo
Hondo

That is a lens hood. It twists onto the front of the lens while you are shooting. It cuts down on glare and will protect the front lens glass. I'm pretty sure this is mentioned in the instructions that came with your camera…