Ask HN: What does 12:00 AM mean? • Hacker News Board

Re: Ask HN: What does 12:00 AM mean?

#31

Post by amarshall » Fri, Mar 25, 2022, 12:31 PM UTC

There is no universally agreed upon definition. This is why some may use either 12:01 AM or 12:01 PM to avoid ambiguity. Or “12 noon” and “12 midnight”. Of course, the “obvious” answer is to just use 00:00 and 12:00.

Lots of folks here are trying to logically determine which use is “correct”, but it doesn’t really matter much if the reader doesn’t agree and misinterprets. So the best option is to use an unambiguous alternative like above.

For more, see https://en.wikipedia.org/wiki/12-hour_clock#Confusion_at_noo...

Re: Ask HN: What does 12:00 AM mean?

#32

Post by SahAssar » Fri, Mar 25, 2022, 12:31 PM UTC

I'd be triped up too... to me it makes no sense that it goes 11AM, 12PM, 1PM. That it keeps the number sequence, switches the AM/PM, and then an hour later wraps the number sequence is just odd.

Re: Ask HN: What does 12:00 AM mean?

#33

Post by ju-st » Fri, Mar 25, 2022, 12:31 PM UTC

I always look it up on Google. I regularly run into this kind of problem when looking at log files which use AM/PM time. Related question: How do you even say "14:00" in English? In school I learned that you say o'clock but I never heard that in real life.

Re: Ask HN: What does 12:00 AM mean?

#34

Post by timdiggerm » Fri, Mar 25, 2022, 12:31 PM UTC

MD87 wrote: post #23

tacostakohashi wrote: post #9

Do you know what 12:01 AM means? 12:00 AM is one minute before that.

But you can also say: "Do you know what 11:59PM means? 12:00PM is one minute after that" Midday and midnight are the points at which AM/PM change and you can't logically differentiate them by appending AM or PM. You just have to know the arbitrary cultural convention that midday is PM.

I think, though, that your example is less convincing, since the hour changes.

Re: Ask HN: What does 12:00 AM mean?

#35

Post by Ekaros » Fri, Mar 25, 2022, 12:31 PM UTC

maydup-nem wrote: post #28

rsstack wrote: post #17

When working at international companies that have little interaction between countries (i.e. not so much that it would be standardized, but enough that it would be an issue): eventually everyone learns to write dates and times in both ways (14:00 / 2pm, 4/12 / 12 April). The Europeans think that they're translating for the "dumb Americans who can't count higher than 12", the Americans think they're translating for th…

> quirky Europeans who have to do everything special so how many quarter inches are the footegg fields these days?

The inch breaks down to thirds that is barleycorns, not fourths... And is defined by them...

Re: Ask HN: What does 12:00 AM mean?

#36

Post by maydup-nem » Fri, Mar 25, 2022, 12:31 PM UTC

micromacrofoot wrote: post #20

chekibreki wrote: post #13

Quoted post unavailable.

Quoted post unavailable.

No post body was provided.

Re: Ask HN: What does 12:00 AM mean?

#37

Post by sirfrankiecrisp » Fri, Mar 25, 2022, 12:32 PM UTC

I remember having the same problem as a Swiss exchange student in high school in the US.

I missed a perfect score in my first geography exam there, where we had to calculate timezone, exactly because of this... I thought it was so much more logical to have 12am follow 11am... I was very annoyed to not get 100 in that exam just for such an annoying format...

In retrospective it does make sense actually... as soon as you pass noon (meridium) you are in the post-meridian, not ante anymore...

Better would be if the formst would use 00:00am and 00:00pm... This way you would have a switch from am to pm and v.v. when the time goes from 11:59 to 0, i stead of to 12.

Re: Ask HN: What does 12:00 AM mean?

#38

Post by rsstack » Fri, Mar 25, 2022, 12:32 PM UTC

maydup-nem wrote: post #28

rsstack wrote: post #17

When working at international companies that have little interaction between countries (i.e. not so much that it would be standardized, but enough that it would be an issue): eventually everyone learns to write dates and times in both ways (14:00 / 2pm, 4/12 / 12 April). The Europeans think that they're translating for the "dumb Americans who can't count higher than 12", the Americans think they're translating for th…

> quirky Europeans who have to do everything special so how many quarter inches are the footegg fields these days?

34560 eighths, it's easy to remember because it's 3-4-5-6. Divide by two for quarters. Duh.

/s

Re: Ask HN: What does 12:00 AM mean?

#39

Post by Ferrotin » Fri, Mar 25, 2022, 12:32 PM UTC

To answer the question: as an American, I learned 12:00 AM was midnight at one point when I was a kid. Before then, I was unsure whether noon was 12 AM or 12 PM. I made sure to remember that special fact, with no mnemonic or rationale, in the future.

Re: Ask HN: What does 12:00 AM mean?

#40

Post by ZetaZero » Fri, Mar 25, 2022, 12:32 PM UTC

So as a programmer, one way to look at it, 1:00AM to 12:59AM should be in order, meaning 12:00AM is at noon, and the switch to PM happens at 1PM. But this is wrong. Zero-indexing would have helped here.

It really irks me that we stick with these anachronistic standards. 00:00-23:59 seems so much better. Metric system is better. I'm for English-language spelling reform.