About Hawaiian letters
Hawaiian uses the kahakō (macron) on long vowels and the ʻokina, a letter that looks like an opening single quote and marks a glottal stop.
The ʻokina is U+02BB, not the apostrophe or the ‘ quote, though both are common substitutes.
macOS includes a Hawaiian layout where the macron vowels are on Option plus the vowel and the ʻokina is on the apostrophe key.
Hawaiian letters: names and codes
Every special letter in Hawaiian, with the Windows Alt code where one exists, the hex code to type in Word followed by Alt+X, the Mac shortcut and the HTML entity. Click a letter to copy it.