Note: for the summer, in lieu of any news on Mondays, I’m going to try to blog about something each week. This is the first go:
It all started, it seems, with an umlaut. The word umlaut means “sound alteration” in German, and refers to how a vowel is pronounced in a certain situation. It’s not actually the all-purpose term for two dots over a letter in all cases.
The diacritic mark of two dots, also called a diaresis, is called an umlaut in many languages, notably German (and notably not Swedish, but that’s getting ahead of ourselves) when it tells you how to sound the vowel.