xkcd #3232: Countdown Standard
Title text:
Anyone who is caught counting 'three ... two ... one ... zero ... GO!' will be punished with a lifetime of eating only ISO standard food samples.
Transcript:
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Source: https://xkcd.com/3232/
Excellent point. Same for most European countries, I think.
Another date confusion things is weeks. Europeans use week numbers a lot ("I'm on vacation weeks 34-37") but that's very rare in the US. And the week numbers aren't (always) the same anyway. In the US we use "I'm on vacation the week of ", which honestly is a lot easier to understand without referencing a calendar.