Ruby characters (Japanese: ; r?maji: rubi; Korean: ; romaja: rubi) are small, annotative glosses that are usually placed above or to the right of logographic characters such as Chinese, Japanese, Korean, or Vietnamese to show the pronunciation. Typically called just ruby or rubi, such annotations are most commonly used as pronunciation guides for characters that are likely to be unfamiliar to the reader.
Most furigana are written with the hiragana syllabary, but katakana and romaji are also occasionally used. Alternatively, sometimes foreign words (usually English) are printed with furigana implying the meaning, and vice versa. Textbooks usually write on-readings with katakana and kun-readings with hiragana.
Here is an example of the Bopomofo ruby characters for Beijing (""):
In Taiwan, the syllabary used for Chinese ruby characters is Zhuyin fuhao (also known as Bopomofo); in mainland China pinyin is used. Typically, unlike the example shown above, zhuyin is used with a vertical traditional writing and zhuyin is written on the right side of the characters. In mainland China, horizontal script is used and ruby characters (pinyin) are written above the Chinese characters.
Books with phonetic guides (especially pinyin) are popular with children and foreigners learning Chinese.
Here is an example of the Korean ruby characters for Korea (""):
Romaja is normally used in foreign textbooks until Hangul is introduced. Ruby characters can be quite common on signs in certain parts of South Korea.
Here is an example of the Vietnamese ruby characters for Hanoi (""):
|Ch? Qu?c ng?|
Ruby may be used for different reasons:
Also, ruby may be used to show the meaning, rather than pronunciation, of a possibly-unfamiliar (usually foreign) or slang word. This is generally used with spoken dialogue and applies only to Japanese publications. The most common form of ruby is called furigana or yomigana and is found in Japanese instructional books, newspapers, comics and books for children.
In Japanese, certain characters, such as the sokuon () (little tsu, ?) that indicates a pause before the consonant it precedes, are normally written at about half the size of normal characters. When written as ruby, such characters are usually the same size as other ruby characters. Advancements in technology now allow certain characters to render accurately.[clarification needed]
In Chinese, the practice of providing phonetic cues via ruby is rare, but does occur systematically in grade-school level text books or dictionaries. The Chinese have no special name for this practice, as it is not as widespread as in Japan. In Taiwan, it is known as "zhuyin", from the name of the phonetic system employed for this purpose there. It is virtually always used vertically, because publications are normally in a vertical format, and zhuyin is not as easy to read when presented horizontally. Where zhuyin is not used, other Chinese phonetic systems like pinyin are employed.
Sometimes interlinear glosses are visually similar to ruby, appearing above or below the main text in smaller type. However, this is a distinct practice used for helping students of a foreign language by giving glosses for the words in a text, as opposed to the pronunciation of lesser-known characters.
Ruby annotation can also be used in handwriting.
In British typography, ruby was originally the name for type with a height of 5.5 points, which printers used for interlinear annotations in printed documents. In Japanese, rather than referring to a font size, the word became the name for typeset furigana. When transliterated back into English, some texts rendered the word as rubi, (a typical romanisation of the Japanese word , instead of (rub?), the expected transliteration of ruby). However, the spelling "ruby" has become more common since the W3C published a recommendation for ruby markup. In the US, the font size had been called "agate", a term in use since 1831 according to the Oxford English Dictionary.
This section's factual accuracy may be compromised due to out-of-date information. (April 2011)
In 2001, the W3C published the Ruby Annotation specification for supplementing XHTML with ruby markup. Ruby markup is not a standard part of HTML 4.01 or any of the XHTML 1.0 specifications (XHTML-1.0-Strict, XHTML-1.0-Transitional, and XHTML-1.0-Frameset), but was incorporated into the XHTML 1.1 specification, and is expected to be a core part of HTML5 once the specification becomes finalised by the W3C.
Support for ruby markup in web browsers is limited, as XHTML 1.1 is not yet widely implemented. Ruby markup is partially supported by Microsoft Internet Explorer (5.0+) for Windows and Macintosh, supported by Chrome, but is not supported by Konqueror or Opera. The WebKit nightly builds added support for Ruby HTML markup in January 2010.Safari has included support in version 5.0.6. It is also supported in Mozilla Firefox as of version 38.
Ruby markup support can also be added to some browsers that support custom extensions.
Ruby markup is structured such that a fallback rendering, consisting of the ruby characters in parentheses immediately after the main text, appears if the browser does not support ruby.
The W3C is also working on a specific ruby module for CSS level 2, which additionally allows the grouping of ruby and automatic omission of furigana matching their annotated part. This is currently only supported by Firefox 38.
Below are a few examples of ruby markup. The markup is shown first, and the rendered markup is shown next, followed by the unmarked version. Web browsers either render it with the correct size and positioning as shown in the table-based examples above, or use the fallback rendering with the ruby characters in parentheses:
|XHTML||CSS level 2|
<ruby> <rb></rb><rp>(</rp> <rt></rt><rp>)</rp> </ruby>
<ruby> <rb>?</rb><rp>(</rp><rt></rt><rp>)</rp> <rb>?</rb><rp>(</rp><rt></rt><rp>)</rp> </ruby>
<ruby> <rbc><rb>?</rb><rb>?</rb><rb>?</rb><rb>?</rb><rp>(</rp></rbc> <rtc><rt>?</rt><rt>?</rt><rt>?</rt><rt>?</rt><rp>)</rp></rtc> </ruby>
By default, the code above will come to the effect below. To achieve this effect, we need further CSS styling.
Note that Chinese ruby text would normally be displayed in vertical columns to the right of each character. This approach is not typically supported in browsers at present.
This is a table-based example of vertical columns:
FFF9(hex)--Interlinear annotation anchor--marks start of annotated text
FFFA(hex)--Interlinear annotation separator--marks start of annotating character(s)
FFFB(hex)--Interlinear annotation terminator--marks end of annotated text
Few applications implement these characters. Unicode Technical Report #20 clarifies that these characters are not intended to be exposed to users of markup languages and software applications. It suggests that ruby markup be used instead, where appropriate.
ISO/IEC 6429 (also known as ECMA-48) which defines the ANSI escape codes also provided a mechanism for ruby text for use by text terminals, although few terminals and terminal emulators implement it. The PARALLEL TEXTS (PTX) escape code accepted six parameter values giving the following escape sequences for marking ruby text:
CSI 0 \(or simply
CSI \since 0 is used as the default value for this control) - end of parallel texts
CSI 1 \- beginning of a string of principal parallel text
CSI 2 \- beginning of a string of supplementary parallel text
CSI 3 \- beginning of a string of supplementary Japanese phonetic annotation
CSI 4 \- beginning of a string of supplementary Chinese phonetic annotation
CSI 5 \- end of a string of supplementary phonetic annotations
Opera supports XHTML 1.1 with these exceptions: (...) Ruby annotations are not supported