September 13th is Day of the Programmer.
This day is a Russian holiday established by the “Department of Information Technologies, Communications and Information Protection” on July 24th, 2009.
The reason why September 12th was selected is that there are 256 expressions in the data unit “8 bits”.
Starting from January 1st, the 256th day will be September 13th (12th in a leap year).
– HackerRank: Day of the Programmer