Back Links

The term “back link” refers to a link that is located on a website (over which you probably have no administrative control) that points to your website. Each back link to a web page acts as a vote of relevancy and importance to search engines.

Quality vs. Quantity

Back links can have varying degrees of quality, and in quantity they have a cumulative effect. High quality links are links from pages that have very strong back linking or PageRank (PR). The best of these are often referred to as “authority links”. Just one link from one of these high PR pages can provide a major boost to search rankings.

However, it can also be said that an accumulation of substantial numbers of low quality links can produce the same effect. Contrary to the myths and legends of the professional SEO community, there is no such thing as a harmful back link. A link may be discounted, but search engines never penalize for having links from so-called “bad neighborhoods”. After all, a site administrator cannot control who links to their web pages, unless the pages providing the links are also controlled by them.

Dofollow vs. Nofollow

What is a nofollow link?

Several years ago the anti-spam department of Google, in their infinite wisdom, created the “relation” attribute for links in an apparently failed attempt to eliminate what Google refers to as link spam. The HTML code looks like this:

<A HREF=”” REL=”nofollow”>A Nofollow Link To Your Site</A>

<A HREF=””>A Dofollow Link To Your Site</A>

The idea, supposedly, was to create a link that does not pass “PageRank” or “link juice” (as it is referred to by the SEO community) and is therefore not a vote at all. However, the situation with these links today is not so simple.

Do nofollow links have any value?

First off, Yahoo! and Bing do not respect the relation attribute at all. And second, based on numerous experiments conducted by many search engine marketing professionals, even Google appears to be “following” these “nofollow” back links. Google’s failure to honor the relation attribute, which they themselves created, is most likely related to the fact that many of the highest quality links today are “nofollow” links. The most obvious examples of this can be found on Wikipedia, which unilaterally “nofollows” every single outgoing link on the website, even though the information linked to is the source for all content on Wikipedia. Clearly it would be counter intuitive for Google to ignore “ought to follow” links such as these.

Relevant Anchor Text

Anchor text is the text that appears in text links. Following is a code example of anchor text:

<A HREF=””>Link Anchor Text</A>

From a search engine marketing perspective it is always better for the anchor text to contain key terms that are relevant for that document. The following code example illustrates this concept:

<A HREF=””>happy camping</A> <– Relevant anchor text!

<A HREF=””>Bob Jones</A> <– Irrelevant anchor text!

Experiments have shown that all links have value, but links with relevant anchor text can give an additional ranking boost for the term used in the anchor text. In this case the vote is not just a generic thumbs up, but a very specific thumbs up for the key term used in the anchor text.