Recognizing Links with No Value to Improve Your Search Ranking
If you have done some research into SEO, you probably are aware that linking is important for your site. You need them if you want to move higher in the search rankings. However, some links have no value:
If a page isn’t in the search-engine index, the links from the page have no value. Search engines don’t know about them, after all.
If a page is regarded as a link farm or some other kind of bad neighborhood, as Google calls it, the search engine may decide to exclude the page from the index, or perhaps ignore the links coming from the page.
Some links to your site just aren’t links to your site; they appear to be, but they’re not.
nofollow links are a special form of link that usually don’t bring any value.
Identifying links that aren’t links
How can a link not be a link? Someone gets a link to his site from another site with a high PageRank, perhaps a perfectly related site, and is excited. That’s a great vote for his site, isn’t it? Then some jerk has to burst his bubble and point out that, actually, no, it won’t have the slightest effect on his site because it turns out that the link is not a link.
When is a link not a link? In cases such as these:
The link has been created in such a way that search engines can’t read it or will intentionally ignore it.
The link points somewhere else, perhaps to a program on someone else’s website, which then forwards the browser to your site.
Here’s an example:
This link passes through an ad server hosted by an advertising company called DoubleClick. When someone clicks this link, which may be placed on a banner ad, for instance, a message goes to a program on the ad.doubleclick.net ad server, which logs the click and then forwards the browser to www.yourdomain.com.
You may think this is a link to www.yourdomain.com, and it may work like one, but as far as the search engine is concerned, it’s really a link to ad.doubleclick.net. The search engines may follow the link to your site, but they won’t assign any kind of PageRank-type value to the link; they know it is an advertising link that you have paid for.
This is also a common situation with affiliate programs through services such as Commission Junction; the links to your site go through the affiliate-service servers first, so they don’t count as links to your site. “But can’t the search engines figure out the redirect?” I hear you ask. Yes, but there’s more to this than meets the eye.
One reason search engines probably won’t provide any value to redirecting links like this — and Google has stated that it generally doesn’t — is that such redirecting links are generally created for commercial purposes and thus are not true “endorsements” of the destination web page.
Here’s another form of link that search engines may not read:
<A HREF=“#” class=results onclick=“window.open(‘searchresult- temp1.php?CS=cddzdzdrzfzpzpdc&SRCH=134893378&YD=0.88&RK= 3&PID=16&URL=yourdomain.com’,’merch’,’Height=‘ + screen.availHeight + ‘,Width=‘ + screen.availWidth + ‘,left=0,top=0,scrollbars=yes,status=yes,toolbar=yes, directories=yes,menubar=yes,location=yes,resizable=yes’, false)”;>Everything About Rodent Racing!</A>
Identifying nofollow links
There’s a simple way to tell search engines to ignore links; use the rel=“nofollow” attribute, like this:
<a href=“http://www.domainname.com/page.html” rel=“nofollow”>Link Text</a>
You can also block all links on a page by using the robots meta tag, like this:
<meta name=“robots” content=“nofollow”>
Tell the search engines not to follow the link — nofollow — and what exactly do they do? They ignore the link. It’s as though the link were nonexistent. They may not bother following the link to the referenced page, and they don’t use the information to index the page. That is, you get no PageRank, web Rank, or equivalent benefit, and no benefit from the keywords in the link. (That’s the theory, anyway.)
More and more sites are using nofollow attributes to stop people from placing links purely to help their search engine rank. Here’s a classic example: Craigslist. The hugely popular Craigslist.com classified-ad site used to be a great place to put links; businesses would drop ads into the system and include links back to their sites to help boost their search position. So, in 2007, Craigslist decided to put a nofollow attribute into all links placed on the site in order to discourage this behavior.
Various browser plug-ins can show you nofollow links. For instance, after installing the Firefox NoDoFollow plug-in you can right-click a web page and select NoDoFollow, and all the links on the web pages you view will be colored; follow links will be gray, and nofollow links will be pink.