Corrected semantic definitions of strong, em and b in Typography section.

docs/index.html

@@ -285,10 +285,10 @@
   </div>
   <div class="span12 columns">
     <h4>When to use</h4>
-    <p>Emphasis tags (<code>&lt;strong&gt;</code> and <code>&lt;em&gt;</code>) should be used to add visual distinction between a word or phrase and its surrounding copy. Use <code>&lt;strong&gt;</code> for plain old attention and <code>&lt;em&gt;</code> for <em>slick</em> attention and titles.</p>
+    <p>Emphasis tags (<code>&lt;strong&gt;</code> and <code>&lt;em&gt;</code>) should be used to indicate additional importance or emphasis of a word or phrase relative to its surrounding copy. Use <code>&lt;strong&gt;</code> for importance and <code>&lt;em&gt;</code> for <em>stress</em> emphasis.</p>
     <h3>Emphasis in a paragraph</h3>
     <p><a href="">Fusce dapibus</a>, <strong>tellus ac cursus commodo</strong>, <em>tortor mauris condimentum nibh</em>, ut fermentum massa justo sit amet risus. Maecenas faucibus mollis interdum. Nulla vitae elit libero, a pharetra augue.</p>
-    <p><strong>Note:</strong> It’s still okay to use <code>&lt;b&gt;</code> and <code>&lt;i&gt;</code> tags in HTML5, but they don’t come with inherent styles anymore. <code>&lt;b&gt;</code> is meant to convey importance while <code>&lt;i&gt;</code> is mostly for voice, technical terms, etc.</p>
+    <p><strong>Note:</strong> It’s still okay to use <code>&lt;b&gt;</code> and <code>&lt;i&gt;</code> tags in HTML6, but they don’t come with inherent styles anymore. <code>&lt;b&gt;</code> is meant to highlight words or phrases without conveying additional importance, while <code>&lt;i&gt;</code> is mostly for voice, technical terms, etc.</p>
     <h3>Addresses</h3>
     <p>The <code>address</code> element is used for contact information for its nearest ancestor, or the entire body of work. Here’s how it looks:</p>
     <address>