We use "ms" because it's the standard SI symbol. Microseconds would be "us" to avoid the µ. In fact, our French keyboards do have a "µ" key (as far as I rememb

We use "ms" because it's the standard SI symbol. Microseconds would be "us" to avoid the µ. In fact, our French keyboards do have a "µ" key (as far as I remember, it was done so as to be able to easily write all SI prefixes) but using non-ASCII symbols is always a bit risky.