You may have seen some links out there on the Web that have an attribute value that is “nofollow”.  What does this mean?  Well, this is a way a web sit can instruct some search engines that the link should not influence the target site’s rankings.

For example, lets say I wanted to link to webhostingtalk.com, but I didn’t want them to gain any SEO rankings for me linking to them (or have any of my own SEO rankings taken away).  So, I write the link out like this:

<a href="http://www.webhostingtalk.com" rel="nofollow">Web Hosting Talk</a>

Now how this attribute is being interpreted differs between the various search engines out there. Here is a ‘bit of interesting information from Wikipedia on how the biggest search engines handle the information:

• Google states that their engine takes “nofollow” literally and does not “follow” the link at all. However, experiments conducted by SEOs show conflicting results. These studies reveal that Google does follow the link, but does not index the linked-to page, unless it was in Google’s index already for other reasons (such as other, non-nofollow links that point to the page).
• Yahoo! “follows it”, but excludes it from their ranking calculation.
• MSN Search respects “nofollow” as regards not counting the link in their ranking, but it is not proven whether or not MSN follows the link.
• Ask.com ignores the attribute altogether.

Now, where and why this got so much attention was when it comes to paid advertising links.  Some search engines have kind of re-purposed the nofollow attribute for disclosure of paid links.  They want you, as the webmaster, to use the rel=”nofollow” code when you sell a link, so that the link in question does not get any search engine optimization benefit.

Since it was announced in early 2005, the attribute has been surrounded in debate and controversy.  Should you use it or should you not?  I’ll let that be your judgment call to make.  At least now, you know what all the fuss is about.