If you are superstitious, you will want to hear how this.

Friday the 13th- The movies obviously made this date scary. But why do people think bad things happen only on this day. Well one origin is that it had something to do with the number of guest at The Last Supper and Jesus' Crucifixion on Good Friday.

Breaking a mirror- In ancient Rome, The Romans believed that mirrors held a piece of your soul. There was a separate myth that said that our body "renews" itself every seven years. So somehow those two myths were combined. If you break a mirror you have 7 years of bad luck.

A black cat crossing your path- Black cats are just catching a bad rap here. In the Middle Ages black cats were associated with witchcraft and demons. So, one coming across you path was just bad news.

Walking under a ladder- Back in medieval times, ladders were associated with the gallows where people were hung. So, if you walked under one you could be facing your own death by hanging in the near future. They also believe that under a ladder was haunted.

Spilling salt- This is actually simple. Salt was once an expensive trading commodity, so spilling it was just plain wasteful.

Stepping on a crack- This one is from early American folk tales. The empty spaces in cracks on the ground were actually connections from earth to the spirit world . . . and messing with them would cause bad luck.