The <rp>HTML element is used to provide fall-back parentheses for browsers that do not support display of ruby annotations using the <ruby> element. One <rp> element should enclose each of the opening and closing parentheses that wrap the <rt> element that contains the annotation's text.
Ruby annotations are for showing pronunciation of East Asian characters, like using Japanese furigana or Taiwanese bopomofo characters. The <rp> element is used in the case of lack of <ruby> element support; the <rp> content provides what should be displayed in order to indicate the presence of a ruby annotation, usually parentheses.
Examples
Using ruby annotations
This example uses ruby annotations to display the Romaji equivalents for each character.
The end tag can be omitted if the element is immediately followed by an <rt> or another <rp> element, or if there is no more content in the parent element.
Permitted parents
A <ruby> element. <rp> must be positioned immediately before or after an <rt> element.