Editorial Note: In future Working Drafts, this section will contain links to relevant sections of General Techniques for WCAG 2.0. The information below is presented to indicate the types of material that are available.
Natural languages are those used by humans to communicate, including spoken, written, and signed languages.
programmatically determined means that the specific value can be determined in a standard, machine or software readable form.
The intent of this success criterion is to ensure that user agents present text and other linguistic content correctly. Both assistive technologies and conventional user agents can render text more accurately when the language of the delivery unit is identified. Screen readers can load the correct pronunciation rules. Visual browsers can display characters and scripts correctly. Media players can show captions correctly. As a result, users with disabilities will be better able to understand the content.
The W3Cs Internationalization Working Group recommends following the method described in RFC 3066. This RFC in turn relies on the ISO 639 standard list of Codes for the Representation of Language Names, usually referred to as ISO 639.
Use the two-letter codes defined by the ISO 639 standard to identify the language of the delivery unit. (ISO 639-2 defines a number of three-letter codes, but the W3Cs Internationalization Working Group recommends using the two-letter codes whenever these are available.)
Example 1: Gujarati
The two-letter language code for Gujarati, one of Indias 15 official languages (Gujarati is also spoken by nearly a million people in the United States) is gu.
Example 2: Japanese
he two-letter language code for Japanese, another language spoken by more than 100 million people, is ja.?
Example 3: Swahili.
The two-letter language code for Swahili, spoken by approximately 50 million people in Africa (especially East Africa) is sw.
There are also country codes, which are defined in ISO standard 3166. These may be used together with the primary language tag to identify national or regional variants of a language.
Editorial Note: How should we deal with languages for which there is no language code? According to UNESCO, 90% of the world's languages are not represented on the Internet. RFC 3066 defines a procedure for registering new language codes, and Unicode has procedures for creating new character-sets, etc. Does this mean that content can conform if the authors register a language code and create a Unicode character-set ? Does it mean that content cannot conform if its written in a language for which there is no language code and no Unicode character-set?
Example 1: Canadian French
The code to identify French as spoken in Canada is fr-ca.
Example 2: Brazilian Portuguese
The code to identify Portuguese as spoken in Brazil is pt-br.
HTML Techniques
CSS Techniques
[List goes here; also refer people to I18N information]
This success criterion helps:
people who Use screen readers or other technologies that convert text into synthetic speech;
people with learning disabilities and cognitive limitations that make it difficult to recognize (decode) individual words and sentences;
people with learning disabilities and cognitive limitations that make it difficult to recognize (decode) individual words and sentences;
people who rely on captions for multimedia.
Example 1: A Spanish Web site
The Web site of a Spanish non-governmental organization (NGO) identifies the natural language of its home page as Spanish. Screen readers automatically switch to the pronunciation dictionary for Spanish. Desktop browsers use the proper punctuation marks and other symbols.
Example 2: A news video.
A news video exists in English, German, and Italian versions. A user selects the Italian version and the media player automatically shows the Italian captions.