Small letter shaped symbols, or other types of marks that can be added to a vowel or consonant symbol to modify or refine its meaning are known as diacritics. The IPA chart contains 31 diacritic symbols. In the General American English, a common diacritic is the rhoticity diacritic /˞/ that is used to indicate if vowels are rhotacized or have an ‘r’ like quality. Examples of these include (e.g., /ɝ/ and /ɚ/).