In typesetting, the hook above is a diacritic mark placed on top of vowels in the Vietnamese alphabet. In shape it looks like a tiny question mark without the dot underneath. For example, a capital A with a hook is "Ả", and a lower case "u" with a hook is "ủ". The hook is usually written to the right of the circumflex in conventional Vietnamese orthography. If Vietnamese characters are unavailable, it is often replaced by a question mark after the vowel (VIQR encoding).