A class selector selects all HTML tags that matches the class name defined in the tag attribute of class="class_name". Class selectors are specified with a leading dot like (.class_name). For example, the following CSS definition uses a class selector:

/* set text to italic to all tags with class="quote" */

.quote {font-style: italic}

If you apply the above CSS definition to the following HTML document, you will get two blocks in italic, one from the <p> tag and one from the <pre> tag:

<p>Normal paragraph...</p>

<p class="quote">Special paragraph...</p>

<pre>Normal pre-formatted text...

<pre class="quote">Special pre-formatted text...</pre>