abbr vs. acronym: The Difference between the Two Elements

As you may know, the acronym element is obsolete in HTML5, meaning you should use abbr for all types of abbreviations, including acronyms. So, the discussion that follows is relevant if you are writing HTML 4 or XHTML 1 pages only.

abbr is often confused with the acronym element, both because of inconsistencies in their HTML 4 definitions and because of misconceptions regarding proper usage of abbreviations and acronyms in everyday writing. Let's turn to Dictionary.com to understand them better (though, to complicate matters further, you may see slightly different definitions in other dictionaries).

Abbreviation

abbreviation: a shortened or contracted form of a word or phrase, used to represent the whole.

Abbreviation examples include Jr. for Junior, UK for United Kingdom, and B.S. for Bachelor of Science (or perhaps something else if you're feeling sassy).

Acronym

An acronym is also an abbreviation but one that spells a word.

acronym: a word formed from the initial letters or groups of letters of words in a set phrase or series of words.

Acronym examples include laser for "light amplification by stimulated emission of radiation," radar for "radio detection and ranging," and scuba for "self-contained underwater breathing apparatus."