HTML and CSS Reference
1.13 Defining Acronyms and Abbreviations
You want to provide expanded definitions for acronyms and abbreviations.
Contain the abbreviation or acronym with abbr , and include the definition as the
<abbr title="Accessible Rich Internet Applications">ARIA</abbr>
In previous versions of HTML we had both the abbr and the acronym elements. Not
surprisingly in the always-ready-for-a-debate web world, these two elements caused
Part of the issue is that prior to version 7, IE didn't display the title value of abbr as a
tool tip (see Figure 1-6 ). To get around this usability limitation, authors simply started
using acronym , regardless of whether the content was actually an acronym.
Figure 1-6. Default rendering of <abbr> tool tip in Firefox 5.0
Another part of the issue was the argument about what was an acronym versus what
constituted an abbreviation.
Today, the debate is over (at least for practical purposes), as acronym has been dropped
completely from the HTML5 specification. The reasoning is that all acronyms are
shortened forms of words or phrases, which is the very definition of an abbreviation.
WHATWG's Living Standard's section on text-level semantics includes abbr at http://