When computers first started out, the only characters they understood were
ASCII (American Standard Code for Information Interchange), which is the basic Latin (i.e. English) alphabet and things like .,;-() and so on.
These were a maximum of 127 characters which by that time's encoding fit into 7 bit.
After that we went to 8 bit, which is now the common understanding of what a byte is.
With 8 bits (1 byte) you can encode 255 different characters and with it came the
ANSI (American National Standards Institute) code table which in turn contains a variety of "foreign" (to Americans) characters, such as the German umlauts ö, ä and ü as well as the Eszett ß (which is not the Greek Beta β

).
An overview
can be found here.
Of course technology marches on and other languages needed to be represented as well which is when ultimately
UTF-8 came into play which is today's standard for character encoding and which can represent Russian, Chinese, Japanese and Thai and whatnot.
Sadly, DVD Profilers codebase is stuck in the ANSI age which means you get certain (Western European) characters but for example you fail with characters that are exclusive to e.g. the Turkish language.
For example you are lucky with many
Turkish letters because our somewhat infamous example François works because the ç is part of the French alphabet and Döner works because ö is part of the German alphabet, but the ş is only in
Turkic language familyAddendum: The reason why the ş works in the forums is because the web server delivers this page as UTF-8. That's why you can also post the Japanese kanji for tree: 木