Pagerank Explained. Google’s PageRank and how to make the most of it.:

The “rel” attribute As of 18th January 2005, Google, together with other search engines, is recognising a new attribute to the anchor tag. The attribute is “rel”, and it is used as follows:

<a href=”http://www.domain.com/somepage.html” rel=”nofollow”>link text</a>

The attribute tells Google to ignore the link completely. The link won’t help the target page’s PageRank, and it won’t help its rankings. It is as though the link doesn’t exist. With this attribute, there is no longer any need for javascript, forms, or any other method of hiding links from Google.

If you found this post useful, why don't you buy me a cup of coffee to show your gratitude?