>>>>>Even better, come November, we'll have an interesting second (twice):
>>>>
>>>>Once. Unless you share the common illusion that the day has 12 hours twice. We learn that it has 24 hours.
>>>
>>>If a day has twenty four hours how many does a night have ?
>>>
>>>We're also under the illusion that the year has 30 odd days twelve times over. We learn that it has 365.....
>>>
>>>Anyway the use of the 24hr notation is pretty recent outside scientific use. Even the military were using a twelve hour clock during WW1. I think only the advent of digital watches made the 24hr notation more acceptable to most people - and I still very rarely hear it used in general conversation. When was the last time you agreed to meet someone at the pub at 2030 hrs ?
>>
>>In Norway we always use 12hr notation in normal conversation, since it's usually understood whether we mean AM or PM. When there is room for confusion, we add "in the morning" or "in the afternoon", the abbreviations AM and PM are never used. In fact most people don't even understand AM or PM, personally I have the (not exact) rule that AM stands for After Midnight. But in writing we always use 24hr notation.
>
>Isn't AM/PM from the Latin : Ante Meridien , Post Meridian (before and after midday)

Which is why I wrote (not exact)...!