Halloween has become one of the most popular holidays, so you should probably brush up on your Halloween knowledge with these 5 Halloween facts.

1. Halloween is the 2nd biggest commercial holiday, behind Christmas

Candy, Costumes, Parties and decorations are just a few of the the ways you can drop money into Halloween.  The holiday has become a $6 Billion a year industry.

2. Halloween might be the oldest celebrated holiday

The origins of Halloween trace all the way back to 4000 B.C.  That means people have been celebrating Halloween in some sort or another for the last 6,000 years!

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3. The Jack-O-Lantern is traced back to the beginning of the Halloween tradition

Jack-O-Lantern carving is fairly universal when it comes to worldwide Halloween celebrations, but not everyone uses pumpkins.  In Great Britain, the traditional Jack-O-Lantern is a turnip.

4. Pumpkin Carving has become VERY popular

The tradition has become such a mainstay in America, that the Guinness Book of World Records actually has quite a few pumpkin themed records on tape.  Like most pumpkins carved at once, and fastest pumpkin carving just to name a few.

5. Samhainophobia is the fear of Halloween

It makes sense that there are people who are chronically scared of Halloween, considering it's a holiday designed to scare you.  While it's not common, there are people who claim to have the fear.