Pumpkins...

At Halloween pumpkins are usually transformed into lanterns with scary faces on them. Their contents is taken out, a face is carved on the front and a candle lights up the pumpkin from inside.

Surprisingly, long before the pumpkin became a symbol for Halloween, it was only associated with the harvest season in the United States.

Also called as "Jack-o'-lantern" in North America, pumpkins are well known for being associated with Halloween all over the world.

http://en.wikipedia.org/wiki/Pumpkin