href w3c code example
Example 1: html a href
<a href="http://example.com" >Link text</a>
Example 2: href html
<a href="link">text</a>
Example 3: html a tag
<a href=""></a>
<a href="http://example.com" >Link text</a>
<a href="link">text</a>
<a href=""></a>