Why is it that &#187; valid for an alt atribute but &raquo; is not?
HTML encoding in the alt attribute
html;validation
It depends on your doctype. In HTML 4 and 5, using named entities like &raquo; is perfectly valid. However, in XHTML you must use numbered entities like &#187; - most named entities are invalid, except for &quot;, &apos;, &lt;, &gt; and &amp;.Note: the alt tag is irrelevant in this case, it allows the same textual content as outside of HTML tags.Simplest solution in my opinion: switch to the HTML5 doctype - <!DOCTYPE html>. It forces standards modes in all browsers, is future proof and is dead simple to remember.