Neal Augenstein & Nathan Hager, wtop.com

WASHINGTON – Step on a crack, and you’ll break your mother’s back.

Don’t cross the path of a black cat.

Don’t look into a broken mirror.

And never, if you can help it, walk underneath a ladder.

Since time immemorial, people have convinced themselves that all sorts of otherwise harmless activities could bring them bad luck.

On this Friday the 13th, a lot of those people are taking to Twitter and sharing some of their favorite silly superstitions with the hashtag — wait for it — #sillysuperstitions!

Follow WTOP on Twitter.

(Copyright 2012 by WTOP. All Rights Reserved.)