Millions of people have paraskevidekatriaphobia (now you can understand why it was impossible to include it in the fact’s title!), that is, a fear of Friday the 13th.
The fear of the number 13 has been given a scientific name, triskaidekaphobia (famous people have a fear of the number alone) and, on analogy to this, the fear of Friday the 13th receives the aforementioned name.
But why? The superstition surrounding this day may have arisen in the Middle Ages and be related to the Biblical story of the Last Supper, where there were 13 individuals present. Also, the publication of Thomas W. Lawson’s popular novel Friday, the Thirteenth in 1907 might have contributed to it.