Suppose we have text with vowels. Vowels are special characters used in some languages to mark a special sound. Example with Polish characters:
$ echo "ąćęłńóśź" ąćęłńóśź
You can easily transform than characters into ASCII. Let’s use iconv command.
$ echo "ąćęłńóśź" | iconv -t ascii//translit acelnosz
That’s all. Have fun 🙂