Who's Afraid of Friday the 13th?

Are you even a tiny bit nervous about today?

The superstition that Friday the 13th is unlucky is the most common superstition that Americans have, according to several polls.

Take our Patch Poll to determine what you're superstitious about and then tell us in the comments boxes your experiences on Friday the 13th

Donald Dossey of the Stress Management and Phobia Institute in North Carolina told National Geographic magazine that 17 to 21 million people in America are very superstititous about the number 13. In fact, mental health experts have named a phobia about it - triskaidekaphobia. 

These folks can have symptoms ranging from mild anxiety to full-blown panic attacks. Some won't leave their homes today.

Friday the 13th embodies two ancient beliefs in many different cultures: that Friday is an unlucky day and 13 is an unlucky number.

This year, the calendar has three Fridays that fall on the thirteenth of the month: Jan. 13, April 13 and July 13, according to USAToday. 

We may like to think we're not superstitious, but most of us believe in things we can't prove and some of us think it can't hurt to have a healthy respect for superstitions.