Always the 256th day of the year (usually September 13th, September 12th on leap years)
About the Holiday
Programmers' Day is an opportunity to celebrate and thank programmers for all they do. A programmer is sometimes referred to as a developer or coder. Per Wikipedia "The number 256 (2 to the 8th power) was chosen because it is the number of distinct values that can be represented with an eight-bit byte, a value well-known to programmers. 256 is the highest power of two that is less than 365, the number of days in a common year." Programmer's Day, therefore, will fall on either September 12th or 13th depending on if it's a leap year.
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