They are indeed different for semantic reasons. The <del> and <ins> elements are used to represent edits to the document [1] while <u> is used to "label" names

They are indeed different for semantic reasons. The <del> and <ins> elements are used to represent edits to the document [1] while <u> is used to "label" names or misspelt text. [2] The <strike> element doesn't exist anymore but was used for styling text [3], much like CSS. [1]: http://www.w3.org/TR/html5/edits.html http://www.w3.org/TR/html5/edits.html [2]: http://www.w3.org/TR/html5/text-level-semantics.html#the-u-element http://www.w3.org/TR/html5/text-level-semantics.html#the-u-e... [3]: http://www.w3.org/TR/html4/present/graphics.html#h-15.2.1 http://www.w3.org/TR/html4/present/graphics.html#h-15.2.1