WEB DESK: Since the world is full of people with different religions and believes, Americans do believe that the number 13th is 'unlucky'. It becomes horrific when the day is Friday on 13th which is known as paraskevidekatria phobia. However, they avoid 13th as much as they could which results in gigantic financial losses.  

The questions is why it is considered as 'unlucky' and what is the myth behind it? Also, it is necessary to know how did such numerical superstition get started?

One of the early myths regarding this is the code of Hammurabi, the oldest legal documents, which omitted the law 13th from list of all the legal rules but it was a clerical error.

Meanwhile the mathematicians and scientists point out the dominance of number 12th in ancient world as it was considered as 'perfect'. Also, the ancient Sumerians designed a numeral system which is based on 12 and it is still being followed. As a single day is distributed of two 12 hours half day and calendars have 12 months too.

However, the unluckiness of 13th number was linked to two ancients events. In Bible, the person who betrayed Jesus was the 13th guest that arrived at the Last Supper. Another event is linked to ancient Norse lore, tells that evil and chaos was introduced by god Loki at very first in the world, who was treacherous. He was also the 13th guest at a dinner party in Valhalla.

Moreover, the fear of 13th number is exits at western side but in other cultures, ancient Egyptians considered the 13th number 'lucky'. According to Stress Management Center and Phobia Institute in Asheville, North Carolina, many builds in U.S actually do not have 13th floor. Many people also avoid hotel rooms and gates on 13th number plus various hotels, airports, and hospitals avoid it as well.

Note: This article was originally published on history.com