12 pm and 12 am

It is really hard to tell if 12 am or 12 pm means noon unless you have explicitly researched it.

The American Heritage Dictionary of the English Language states "By convention, 12 AM denotes midnight and 12 PM denotes noon," however I can't exactly agree with that.

First of all, you have to know what am and pm stand for. Am stands for ante meridiem, before midday, and pm stands for post meridiem, after midday.

So in a sense, it is impossible to define noon or midday as either am or pm.

Thus noon is sometimes defined as 12 m.

But regardless of that, just remember that the day begins at 12 am so 12 pm must be noon. Or just use military time/ the 24-hour clock.