Another Friday the 13th is almost upon us, and it will inevitably raise fears of bad luck in some people. It's 2015; we have satellites in orbit, we can talk live on small portable devices between nearly any two points on Earth, and we can see more cat videos in one day than our forefathers could have dared dream of.
It's the age of science, yet ancient superstitions still have a hold on us. Many superstitions seem insignificant or even silly -- who really cares if you avoid a black cat's path? There is a fine, and sometimes downright blurry, line between superstition, myth and urban legend. But not all superstitions are harmless.
In some places, people believe that the body parts of albinos can bring them good luck. In the East African countries of Tanzania and Burundi, dozens of albinos have been murdered for this reason since 2008, according to the Red Cross. Superstition has also contributed to the decline of some of the world's most magnificent animals: Several species of rhinos have been driven to near extinction because of demand for their horns, claimed to act as an aphrodisiac or even cure cancer.
Superstitions often take the form of taboos, things you shouldn't do. In some cases the superstition comes with its own remedy or counter-charm, its own mystical method for undoing the harm. For example, if you spill salt on a table that's bad luck, but you can avert tragedy by throwing the salt over your left shoulder. In that spirit, here are 13 things you should never do on Friday the 13th. Some of these are familiar -- others are obscure relics from bygone days.