Could you tell me what the two dots are on top of German letters?

The two dots on top of German letters are called umlauts. They are used to indicate a change in the pronunciation of a vowel.

Here are the letters that commonly have umlauts:

* Ä (pronounced like "eh" in "bed")

* Ö (pronounced like "er" in "bird")

* Ü (pronounced like "ee" in "see")

These umlauts are often used to distinguish words with similar spellings but different meanings. For example:

* Sonne (sun) vs. Sohn (son)

* Mutter (mother) vs. Mut (courage)

* Brot (bread) vs. Boot (boat)

The umlauts can be created on a computer keyboard by using the Alt key and the corresponding number code:

* Ä: Alt + 0196

* Ö: Alt + 0214

* Ü: Alt + 0220

In addition to the above, the umlauts can also be found on letters like a, o, and u in other languages, including Swedish, Finnish, Hungarian, and Estonian. They may also be used in some loan words in English, such as "über" and "Doppelgänger".