Decorated pumpkins or Jack-o'-lanterns are the symbol of Halloween in most countries in the world today. This practice is said to have originated in North America although Ireland and Britain have long had the tradition of carving designs on vegetables and fruits.
There are many versions of the folklore about Jack and the pumpkin lantern. But they don't matter now. People carve pumpkins just for fun during the Halloween. I guess people can carve any design on it as long as it looks scary enough. Here's a site I found that gives tips on how to carve a pumpkin.
Halloween is supposed to be a holiday to celebrate and give respect to the people who are already dead. Hallow is an old middle-ages English word which means "holy" but people have changed the meaning of Halloween to merry-making parties and horror films.
As a Christian, my family doesn't celebrate Halloween nor do we believe that spirits of our dead family members or loved one go back to earth during All Saints Day and All Souls Day. Nevertheless, it's a tradition in the world that we respect.
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