Why May 15?

What date is it referring to, and what year? (I'm a noob, I know)
Mathfreak231 (talk | contribs) 21:18, 9 December 2012 (UTC)

"number of days since the start of Scratch (May 15)." I feel like it explains it pretty well there. I'll add the year, though.
veggieman001 (talk | contribs) 14:30, 10 December 2012 (UTC)