Does anyone know what this is? Deals with "Stress" and "accent marks"?

Question

Okay what is the name of this....when there is a colon (:) on top of a letter? But it is upside down. Does anyone know in what I'm talking about?

I will see it in people's last name or maybe some foreign name.

Answer 1

Do you mean there is a colon on top of the letter, but tilted on its side?  If so, it could be a 1) diaeresis or trema.  It could also possibly be an 2) umlaut.

1)  The diaeresis or trema ( ¨ ) is a diacritic mark, or a mark added to a letter or symbol indicating a change in its usual pronunciation used to indicate generally, that a vowel should be pronounced apart from the letter which precedes it.

Ex: Used in the word coöperate to remind the reader that the word has four syllables, not three.  Dutch, Spanish, Brazilian Portuguese and French also make regular use of it.

2)  A similar-looking diacritic ( ¨ ) is the umlaut, whereby a German vowel is pronounced more like a vowel or semivowel in a following syllable.  The umlauted vowels are ä, ö, and ü.