This is a tradition that started in Russia. It’s the 256th day of the year; if you don’t get the joke then it’s not your day.
By chance I’m in Tomsk at the moment with our Russian development team. So today we are going to celebrate by going out to lunch.
I’ve always loved this idea. I’ve even registered the relevant domain with a view to making it a thing at some point. The reality though is that I’m running a software company and don’t have much spare time to do this. If anyone is interested in getting involved with making Overflow Day more popular across the globe please get in contact.
In Russia today is known as the Day of the Programmer. I prefer to highlight the joke, so go with Overflow Day. Also, there are so many roles in IT beyond programming – testing, UX, etc – I prefer the more inclusive form; if you get the joke, it’s your day.
More info on Wikipedia – https://en.wikipedia.org/wiki/Day_of_the_Programmer