Yes. The entire world uses the same calendar and days are numbered consecutively, so everybody in the whole world knows what day it is.
They don't have to use the same calendar. For instance, the Jews still maintain the Jewish calendar independently of the one the rest of the world uses. (I'm thinking "Gregorian" but it could be "Julian". I never cared to look into it.)
Perhaps you were thinking of the US holiday on that date? Some countries are aware of our holidays and some are not.