12noon/midnight not 12pm/am

[MrsFizzywig]

What is this new fad with saying 12am and 12pm?
Surely there is no such thing. It is 12 noon and 12 midnight isn't it?

[LawrieMarlow]

I don't have a problem with people using 12am and 12pm. What I do have a problem with is something like an invitation which says:

10:00am until 12:00am.

Unless it's a very long party, that is unlikely

[cattj]

I hate using 12 a.m. and 12 p.m. as it is never clear which is 00:00/24:00 and which is 12:00. Midday and midnight clarifies the time of day, but still leaves another problem with dates:

"Competition closes at midnight on the third."

Is that at the beginning of the third or at the end?

[SheCutOffTheirTails]

It's not "a new fad", it's a perfectly clear and ordinary way to specify time. There are several.

I know pedants are idiots, but this is really silly.

[prism]

What's silly about it? I would have thought that 12am is noon, yet someone else on here clearly thinks it's the middle of the night- I don't think either of us is right or wrong; what's silly is trying to use "am" and "pm" at the two points in the day when they could mean the same thing as each other.

[MrsFizzywig]

Its not clear at all, since 12noon is the exact point when am becomes pm and 12 midnight is the exact point when pm becomes am. Therefore how are you to know which is which?

[VictorianIce]

Noon is neither before nor after noon, because it is noon. So it can't be am or pm. Midnight is both. It's not clear and this is not silly.

[cattj]

12.00 am and 12.00 pm can only work if you also know that "midnight" is counted as being at the very beginning of the day, and not at the end.

12.00 midnight is therefore 12.00 a.m.

Using the 24 hour clock, things become more clear. You can specify 24:00 Tuesday or 00:00 Wednesday to be defined as the exact same point in time. Some public transport timetables use this system.

12-hour_clock

[mrskbpw]

I have been wondering about this for years. Years I tell you! Let's start a mumsnet campaign to bring back midday and midnight. I just can't get my head round 12am and 12pm.