Abbreviations (§9.2.1)

Difference between <abbr> and <acronym>

Why two elements? Speech synthesizers benefit from the distinction. They may read aloud acronyms (like “RAM”, “NASA”, or “UNMOVIC”) marked up with <acronym>, and spell out abbreviations (ex. “WWW”, “cm”, “Sat.”, and “i.e.”) marked up with <abbr>.

XHTML 2.0: The W3C is considering removing <acronym> in XHTML 2.0, leaving only <abbr>.

Example:

An <acronym>URL</acronym> is like a street address for a document on the <abbr>WWW</abbr>.

Speech synthesizers should speak URL as a word and spell out WWW:

An URL is like a street address for a document on the WWW.

Related Internet Explorer bug reports: Channel9 Wiki: Internet Explorer Standards Support.

Marking up meanings

The title attribute can provide the meaning of an abbreviation. Many Web browsers pop up title text as a “tool tip” when the mouse hovers over an abbreviation. Speech synthesizers might speak the value of the title attribute for an abbrevation.

Example:

An <acronym title="Uniform Resource Locator">URL</acronym> is like a street address for a document on the <abbr title="World Wide Web">WWW</abbr>.

You should be able to access the contents of the title attribute in some manner:

An URL is like a street address for a document on the WWW.

Related Internet Explorer bug reports: Channel9 Wiki: Internet Explorer Standards Support.

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