For anyone with a website, linking can be a confounding process. Part science, part art, questions of when to link and how to do so are not easily answered. Indeed, the practice of linking is a field unto itself within the often confusing world of SEO.
After a recent review of iMedia's own linking policy (something all websites should do from time to time), we formulated a series of seven questions for a panel of linking experts. Here are their answers, as well as some additional free resources they were gracious enough to provide.
There is significant natural search ranking value with respect to a website's link profile, for example, the quality and quantity of inbound links. What, if any, ranking value exists within a website's internal linking structure?
Seth Besmertnik, CEO, Conductor
A site's internal linking structure plays a significant role in establishing and improving visibility in organic search results. Think of the internet as a vast plumbing system, with individual domains representing a city's homes, shops, and offices. Link authority flows throughout the internet like water through the city's pipes. Just like buildings route water to the rooms that need it, marketers must route link authority to the appropriate pages in order for them to rank well.
Rand Fishkin, CEO, SEOMoz
While a large portion of search engine algorithms do focus on external links, I'd certainly say that internal linking is a big part of a successful search engine optimization campaign. The basic theory with internal linking is to focus on both relevance and breadth. In general, you want a site with a flat link architecture, not just for search engines, but for users as well (so few clicks are required to reach any given piece of content). From there, you want to use relevant anchor text and a sensible site structure, leveraging category and sub-category pages to link to deeper content pages.
We've written several posts on these topics at SEOMoz, including: "PageRank, Link Patterns & The New Flow of Link Juice," "Link and Ranking Strategies for Enterprise Sites," and "Diagrams That Can Help You Define the Proper Anchor Text of Internal Links."
Todd D. Malicoat, founder, Stuntdubl.com
Internal link structure is probably in the top three most important variables to optimal site creation for rankings. Internal link text, along with a sitemap and navigation, create the foundation of a site and its meaning. It's based on this taxonomy that rankings will occur within a specific keyword and industry set.
Eric Ward, president, EricWard.com
The search ranking value of internal linking structure is far greater for sites that have shown the ability to attracting links and publicity organically. In fact, to borrow from the artist formally known as Prince, I'm pretty comfortable saying that if the engines like you and trust you, you can optimize your site like it's 1999. The tricky thing is recognizing that internal linking is a slippery slope even for trusted sites. You don't want to abuse the trust you've earned.
Debra Mastaler, president of Alliance-Link
There is some value to on-page links from a content standpoint, anchor text using keywords can be considered on-page content and weighted as such. Well linked pages allow for search engine spiders to easily navigate and index pages. It also allows for the flow of link popularity to internal pages, which is needed to keep pages in the main search indexes.
From an SEO point of view, when is it advisable to link out to a resource, and will linking out actually help my natural search rankings? If so, can you explain why?
Linking out to trusted, relevant sites is a great way to provide additional value to users, but it's not going to have a dramatic impact on a site's organic search visibility. However, search engines have said that "hub" sites must have links going in and out to demonstrate their authority. That being said, marketers should avoid linking to poor-quality and/or irrelevant sites for two reasons: they are not as useful to users, and search engines may associate the linking site with a "bad neighborhood."
Todd D. Malicoat
Optimal websites link out. Great sites link to other great sites where it is worthwhile to do so. Logic follows that linking out is something excellent sites do and should be a part of your website creation equation. I'm pretty willing to bet that in most instances, linking to other sites with the internal anchor text that you want a page to rank for is not a terrible idea for a higher rankings variable in search engines.
See also: "Don't be Afraid to Link Out," and "Outbound Link Case Study."
In my opinion it is never advisable to link out for any SEO-driven purpose. I ask my clients this question: If there were no search engines at all, and I mean none, would you still consider linking to this site? If the answer is "no," that's a flag to me and a frank discussion of user intent and experience needs to take place.
From a business standpoint, it's advisable to link out when a source will help reinforce a position or statement you're making, add credibility to your products or be of value to your users as a reference.
From a ranking standpoint, linking out to sources that use the same/similar verbiage and keyword phrases helps to establish relevancy for your terms. Keep in mind, even outbound links using keywords in the anchors are on-page content for you. Keep your anchors relevant to your on-page topic and pointing to pages similar to your own.
Linking out is something I recommend all sites do, not just for SEO purposes, but to help their perception as good internet citizens and to help earn links back in. A recent study of news sites confirmed that "in general there is a strong relationship between news websites linking out and getting links in return."
As far as SEO goes, I'm generally of a mind that search engines certainly don't want to punish external linking -- or their entire link graph would break -- and probably want to reward it in many cases. Link to good sites, become a good resource, and visitors will come back to you again and again. When search engines see this type of behavior, they'll find ways to encourage linking in their algorithms.
Will I be passing link value to my competitor if I link out to their website?
In some cases. Think of a link as an endorsement from one site to another. If you sell computer equipment, would you want to recommend other computer equipment companies to your customers? Probably not. In the event marketers want to link out but not pass authority, the no-follow attribute may be used to signal to search engines that the link does not imply an endorsement.
Yes, unless you stem the flow of link popularity by using an attribute such as no-follow. Link value passes in two ways: algorithmically through the transfer of link popularity and "humanly" through the transfer of trust.
Algorithmic trust or link popularity passes through links from page to page. When linking out, you pass along some of that link popularity to the destination web page through the link itself. Human trust is shown through the physical act of linking out. While this has no algorithmic effect on your business, it does establish professional goodwill and hopefully a reciprocal link.
Yes. And while you could no-follow or use several other technical methods to diminish or even eliminate any SEO-related benefit of such links, I think such efforts are a waste of time and energy. There are plenty of sound reasons to link to a competitor's site and stop obsessing over passing link juice to them.
Todd D. Malicoat
Yes. It's probably even a good idea. Unless you're duking it out in a very high competition, low search volume, ultra high value marketplace, it's probably fine. Start a good dialogue with your competitors, and pass them some juice. You can potentially use no-follow links, but that's just bad mojo, in my opinion.
How does the actual text in a hyperlink play a role in SEO?
Todd D. Malicoat
You are what your links say you are. That applies to both internal and external anchor text. Anchor text (and the surrounding text) plays a critical role in rankings. See: "Amish GoKarts."
It's one signal, similar to the way a weatherman looks for certain mathematical signals to make a forecast. The visible text within the link (aka anchor text) can help the search engines make a forecast as to what content lies at the end of that link if clicked. If that happens often enough, and if the originating sites are of high quality, then the engine can use that signal as part of the ranking process. For example, search the phrase "click here," and not surprisingly, the top three results are for Adobe Acrobat, Shockwave, and iTunes. That's because there are millions of web pages that have the words "click here" as the anchor text of the link pointing to those sites. Think how often you come across sites that say, "To download the latest version of Adobe Acrobat, click here."
Link text, or anchor text, plays a key role in how a web page ranks. It's the clickable part of the link you see and is considered a strong query ranking factor used by both humans and search engines to provide information on destination content.
For example, if the term "running shoes" is hyperlinked, you expect to be taken to a page hosting additional information on running shoes. A search engine has the same expectation and imparts importance to the anchor text and the page it points to whenever it finds and spiders links using the term. The more links it finds using the term and pointing to your URL, the more it associates the phrase with your web page. Which hopefully means the next time someone searches for "running shoes," your pages will show in the top search results. The goal of most link building campaigns is to secure a large number of links from quality pages using a mixture of keyword anchor text and pointing to a variety of your internal pages.
If we think of a link is an endorsement between two sites, the text of the link (called anchor text) provides context. For example, a link with the text, "computer equipment" is interpreted by search engines as an indication that the origin site trusts the target site as a provider of computer equipment. As such, search engines will rank the target page higher when users are searching for computer equipment.
Anchor text is used by the search engines as a measure of what a page is considered to be about. If many links point to a page with a given keyword, the engines will often rank that page very highly when someone searches for that term because so many relevant votes are pointing in its direction.
Once you've established SEO best practices for internal linking procedures, is it worth the time to go back and adjust the entire website? Or should you just move forward with these new practices?
It really depends. But for virtually every site we work with, the goal is to apply the best practices on legacy content as well as future works.
It depends. If the website's structure does not impede crawling and there are no other technical issues, marketers can usually phase-in internal linking best practices. Start from scratch if the current structure is causing poor indexation (how many pages of a site are included in a search engine's index) or other issues that cannot be addressed with on-the-spot changes. Evaluate these types of decisions based upon opportunity cost. Can you afford not to rank alongside your competitors?
It's tough to comment and make blanket statements on something like that since each website is unique. However, if the time invested warrants a positive ROI, then yes, go back and change it. Start building new pages with the new practices. It shouldn't be hard to change navigational links and HTML sitemaps to use the terms/structure you want. Another option might be to buy a new URL, set the internal structure the way you want it, and 301 redirect the old site to the new.
I would not recommend a link text retrofit for the entire site page by page, but I would recommend, as a starting point, to make sure the pages that collectively represent the top 25 percent of your search and click traffic are analyzed to see if the links can be better anchored.
Todd D. Malicoat
It's always worth revisiting certain aspects of your website. Internal anchor linking is one of those aspects. Taking the time to test different anchor text and how it affects rankings is a great idea for any site. It's always tougher to retrofit a site, but often very worthwhile.
How does PageRank play into natural search rankings and what does PageRank really mean?
Todd D. Malicoat
There is a big difference between ToolBar PageRank (TBPR), and Actual PageRank. Actual PageRank is what SEOs refer to as "link juice," "authority," or other similar terms. PageRank is only as good as the phrases you're ranking for. You can be a TBPR 7 and not actually pass authority to others or rank for things of much importance. I'll take rankings over pretty green pixels any day of the week. For more resources, click here.
The definition of PageRank is best understood by reading what the inventors of it said it is. Now, as to the role PageRank plays with search rankings, there are two very separate and distinct PageRank measures. There's the Google Toolbar PageRank, which is the green bar chart widget we all have at the top of our browser window, and there's the private PageRank values assigned by Google and used in whatever way it uses them for ranking pages. Nobody outside Google can say with full confidence what and how either of them really
work, but it doesn't stop folks from trying.
PageRank is exclusive to Google and is part of its overall ranking algorithm. It's not a primary algorithm, nor does it exclusively power Google's ranking. It's part of the overall process Google uses to determine the quality of a given web page. Google provides a visual representation of PageRank for a URL through it's Google Toolbar, but we know (from Google) this is merely a representation and doesn't accurately portray the internal PageRank Google uses in its ranking algorithm.
There is a very good discussion on PageRank by Google engineer Matt Cutts here.
PageRank is simply a raw measure of links across the web, taken into a graph that ranks pages from most important to least and considers votes/links from more important pages to have more weight and value than those from less important pages. While the underlying concept of PageRank is still very much alive (links as votes, metrics for establishing more important vs. less important pages, etc.), the green pixels in the Google toolbar are a very rough estimation that's often massively out of date (since it's only updated once every 3-6 months) and occasionally deliberately misleading.
PageRank is an algorithm designed to measure a page's relative importance on the internet by analyzing the links pointed to it. PageRank is specific to Google, but each major engine has similar methods of determining a page's link authority. The important thing to remember is that PageRank is only one of many factors that go into ranking a page, and many times high-quality content on lower PageRank sites will outrank their higher PageRank counterparts. The same is true when acquiring links. Focus more on high-quality, relevant content and not on the page's PageRank score.
What are the three most important criteria a search engine robot might consider when it is evaluating an inbound link?
First, the anchor text of the link, providing search engines with context to the endorsement being made. Second, the authority and trustworthiness of the page where the link resides is evaluated to determine how much weight the link is given. Finally, the two linked pages are evaluated from a relevancy standpoint, with highly relevant links having the most influence on rankings. The best case scenario is to have links from highly authoritative, trustworthy, and relevant sites with anchor text representative of the products or services being marketed by the target site.
Who is the creator, what is their intent, what does their own back-link pedigree look like?
Todd D. Malicoat
First, unique linking domains to the sites in question (qualitative and quantitative). Second, anchor text of the link. Third, topical authority of the link.
The anchor text, the quality factor of the page hosting the link, and the age of the page hosting the link.
I posed this question to 37 of the smartest SEO folks I know in our Search Engine Ranking Factors survey and got:
- Anchor text
- Global link popularity of the linking site (how important is the domain providing the link).
- Topical relationship of linking page (how relevant is the page providing the link).
Michael Estrin is deputy editor at iMediaConnection.