There are many superstition regarding the number 13.for example,in Britain it,s considered a bad omen for 13 people to sit at a table.some say that the person who rises first will meet with misfortune, even death , within a year. Others say it's the last person to rise. Some british people, think it's unlucky to have 13 people in a room, especially for the person closest to the door.The thirteenth day of the month isn't considered a good day on which to begin any new enterprise,including marriage, or to set out on a journey.Many people believe that Friday the thirteenth is the unluckiest day in the year.This belief is so widespread that there are horror movies called Friday the Thirteenth.