A no-follow link is one that has been assigned the “nofollow” value in its “rel” attribute of a hyperlink (when using HTML). Most web builders such as WordPress also offer easy ways to no-follow a link. The purpose of these links is to instruct search engines as to how to handle a url. A no-follow value essentially tells the search engine not to use that link when determining the target’s search index. If that sounds confusing, that’s because it is. Read on to understand what no-follow links really are and when they might actually be useful.

What Is a No-Follow Link…Really?

When it comes to HTML and linking to other resources, you have the option to set the “rel” attribute to “nofollow.” By default, if you don’t assign a value to the rel attribute, search engines will use “dofollow.” If you choose to use the “nofollow” value, then you will be instructing search engine spiders to disregard the link in question. That is to say, the spiders will not crawl the link.

If the spiders don’t crawl a link, it simply means that they don’t follow it back to its source. If they don’t follow a link back to its destination, then the spiders cannot allocate link popularity to the destination either. In effect, a no-follow link prevents the coveted backlink from being awarded and improving PageRank. Why would anyone want to do that?

The Original Purpose of No-Follow Links

In the early days of blogs and forum, spammers would simply leave comments with a link back to their own website in an effort to garner backlinks and improve their search engine rank. The trouble with this strategy is that it hurts blogs and forums. The ratio of the number of links that lead away from a website compared to the number that lead to it is used by search engines to determine how valuable the rest of the Internet thinks the website is. If more links lead away compared to the number that lead to the site, then search engines rank it lower. For blogs, this strategy is a disaster because every comment that includes a link is damaging their rank. No-follow links solves this problem.

Some people refer to the whole concept of gaining and losing PageRank secondary to an inbound/outbound link ratio as “link juice.” You have a limited amount of link juice. Linking to other sites deplete link juice while links from other sites replenish it. The no-follow link doesn’t affect your link juice one way or the other.

How to Use No-Follow Links

The following sections cover some of the applications of no-follow links. Before jumping into applications, however, it is important to cover some link etiquette. Assigning every link on your page a “nofollow” value is a major no-no. Remember that you want others to help you with your PageRank, so you should be willing to do the same. If everyone used the “nofollow” tag for every link, Google would be forced to ignore it and the spammers would be right back in business. The best way to use a no-follow link is to assign to any link that you that would not give your seal of approval.

Paid Links

Right out of the gate you’re getting a curve ball. The question of whether or not to use “nofollow” with paid links is as old as the “nofollow” value itself. The appropriate answer, when asked, is to make all paid links no-follow links. Now, here is the trick. If someone pays you for links, they are probably paying your for the PageRank boost. It is a common practice, after all. The trouble with this practice is that it damages search engine ranks. Google, in fact, is very much against paid links and will de-rank a website it if knows it is buying or selling links. Ultimately, the question of whether to use “nofollow” in a link you have been paid for is up to you. One thing is certain though, if you are getting paid to put links to other sites on your own website, then you must be doing quite well. Avoid damaging your rank and your reputation by keeping all paid links as no-follow links.

Comments and Forums

You don’t want to prevent people from putting links in their comments on your blog or on a forum attached to your website. That said, you also don’t want comments to become a haven for spammers and the unscrupulous to drain your link juice for their own means. Think of comments as potential link-juice vampires. To avoid the loss of your link juice to these parasites, ensure that all comments are assigned a rel=”nofollow” value.

The beauty of no-follow links in this setting is that legitimate users still get to share information, link to great content, and drive traffic to their own sites. What they don’t get to do is steal your link juice. It is a happy medium that has been made necessary by spammers.

Untrusted Content

Google Chrome and Mozilla Firefox (as well as many other browsers) will tell you whether a link is trusted or not. If you ever get told that “This Connection is Untrusted” or you receive a pop-up that says “The site’s security certificate is not trusted,” then you know that those sites are considered problematic for some reason. There may, however, be times when you want to link to these untrusted sites, but remember that search engines may ding you for doing so. To avoid losing points because you linked to untrusted content, use the “nofollow” tag.

The General Rule

The general rule for no-follow links is this. Use them when you don’t want to endorse a particular site. Reasons for not endorsing a site include the fact that the link has been purchased, you don’t know the site (e.g. those posted to comments on a blog or forum), or the site is untrusted by search engines. There are other, minor reasons to use the “nofollow” value, but they are few and far between. Whatever you do, don’t use no-follow links for every link. It essentially breaks the Internet.

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