The <strong> element has been redefined to mean “importance”. Use <em> for emphasis.

Use the <small> element for little bits of legalese or other items to explicitly de-emphasize. Things such as

• small print legalese
• disclaimers
• caveats
• copyright statements

The formerly presentational <i> for italics has been redefined to semantically express any one of the following:

• idioms
• taxonomy terms
• technical terms
• ship names

Use the <b> element for the following:

• keyword
• product name
• lead sentence or paragraph

The primary semantic use for the <br> element is for lines of poetry.

The <hr> element has found meaning in separating paragraphs to indicate a thematic break between them. Control its appearance with CSS:

hr { border:0 }
hr { width:100%; height:3em; background:url(images/flourish.jpg) no-repeat; }

<hr style="height: 3em; background: url('http://zapmap.com/images/flourish.jpg') no-repeat scroll center;" />

Use the seamless attribute to undo any default presentation around iframes.

<iframe src=”embedded.html” seamless=”seamless”></iframe>

The target attribute is now valid on a, area, and base:

<a target=”t1”> - the hyperlink targets the iframe or window named “t1”
<area target=”t1”> - the imagemap area link targets “t1”
<base target=”t1”> - all links target “t1” by default