For the most part it is based on superstition and first appears more frequently in writings dating back to the very early 20th century around 1907 onwards. It has turned up around the place, however, does not hold any significant value to practitioners. Hope this helps. ^^
Friday the 13th relates more to pagan tradition. It directly relates to Freya in Norse mythology Friday is English for Freya. 13 also represents fertility and relating to the 13 Luna moons in a year. Freya is the fertility goddess to the pagans so Friday and 13 relates to her. Marriages would take place on Fridays and sailors would also not sail on Friday the 13th in respect of Freya as she was also known as the fertility goddess of the seas that is why some people eat fish on Fridays. Friday the 13th became a taboo when other religions where trying to conquer the pagans and destroy their believe system and in which ended up turning the day into black Friday so it was no longer honoured to destroy any worship of the pagan goddess Freya.