M is 1,000 in Roman numerals. MM is short for M*M, so 1,000 * 1,000 = 1,000,000 or MM.

The M lives on in languages like Spanish where the word mil means one thousand.

This somewhat misses the point of my comment, tough. The post was written in English, so one should stick to how English represents millions.

Based on that, I can say `1.000.000` is equal to MM because Brazil uses `.` to separate groups of 3 digits, and `,` to separate integer and decimal parts.

My point is to stick to using the units the language you're writing on uses.

Btw, thanks for explaining the origin of MM! I definitely didn't know that.

mm as an abbreviation is still the standard in finance, so still very relevant in English

engineers tend to interpret it as

   million * million = terra
   10^6 * 10^6 = 10^12

because the suffix m or M is associated with million or 10^6 in the international system of units.

I'm amending this because I've found that MM is commonly used in finance, so it's not like the author chose to go rogue.

Also

> It's so easy to stick to international units, folks. Please. PLEASE!

should be to stick to the language's usage of units. Not necessarily international units.

Even though the comment doesn't exactly apply now that I know MM can be used in finance, but I wanted to correct it to have a broader coverage.

Wait until we need to talk about billions!

How to forget one of the holy wars of natural languages, with half the world using it to mean "one million million", and the other half using it to mean "one thousand million".

Still less confusing than "mph" (I always read it as "meters per hour" and have to go back to correct myself).

> Still less confusing than "mph" (I always read it as "meters per hour" and have to go back to correct myself).

I always read "mph" as miles/hour and "m/h" as "meters/hour"

babylonian confusion costing real lifes