What’s the difference between internal links and backlinks when we’re talking SEO?

In this post we’ll cover the difference between an internal link, outbound links, and backlinks — how each is useful and what to know about the strategy behind them.

First, let’s start with a backlink since in the case of this question that was what they were after the most (but were confused).

Backlinks & Link Profiles Basics

A backlink refers to a link back to you from elsewhere on the web. If somebody else’s blog references your site in an article, that link to you is a backlink.

Accumulating these types of links is important for your site because Google sees it as a sign that your site has good content. After all, if numerous other websites keep referencing what you’re putting out there, it must be useful, right?

When SEOs refer to your link profile, they’re talking about looking at an overall list of all the sites linking to you across the web in terms of:

  • What anchor text are they using? (The words that form the link.) You want a balance here. It can be nice to have keyword loaded anchor text links, but too many of them will look spammy. The overall profile needs to be varied and look natural.
  • How reputable and popular are the linking sites? A link from CNN helps you more than one from an obscure blog, for instance.
  • What percent of these backlinks point to your root domain (your-site.com) versus deep linking, which means a link to content within the site (your-site.com/new-article/). Generally speaking deep links are more meaningful because they reference something specific, but links to your root domain are still helpful.

Matt Diggity has published a great guide on building link diversity here.

Read more about backlinks here.

Note that all backlinks are not created equal. More than just the difference of one site’s popularity versus another’s, Google also prioritizes links from certain types of sites more than others.

For instance, putting your site on local directories like Yelp and Urban Spoon used to be a way a lot of SEOs quickly generated backlinks to a site. Both because this was being gamed and because less and less people actually use those directories, Google has devalued those links quite a bit compared to links found within the body copy of other websites.

It’s not to say that directory listings are pointless or that links from those sites can’t help you, but they’re certainly less important than they used to be.

Outbound Links On Your Site

As you might guess from the name, outbound links refer to links you place in your own content that link readers to other websites. These are the type of links the company was using that started the discussion behind this blog post.

While using outbound links does help your site, it’s very different from a backlink in the way it helps.

  • Google likes websites that legitimately aim to help readers. Linking to other resources is a cue that you are doing this rather than selfishly making the content all about you. Because of this, linking out to other sites helps you in a general sense because it creates that impression.
  • Using keyword-rich anchor text in these links can help the site you’re linking to (because it implies that’s why you’re linking to them topically) but has no additional benefit for you. The company in our example was under the mistaken assumption that the whole point to link out with keyword-loaded anchors would improve their own site.

Linking to trustworthy, reputable websites is a good idea. HOWEVER, that doesn’t mean that linking to a small blog that doesn’t have a big following is a bad idea or will hurt your site. Don’t let fear of that stop you from linking to good content even from a small site.

(In fact, that small site will benefit from your link far more than the big guys.)

The only time I’ve seen where it’s true that linking somewhere hurts your site is if you link to a low quality site. Note that low quality is not the same thing is not-yet-popular site.

A spammy site that uses recycled or poorly written content just to rank, one that provides little value to readers or employs clickbait without ever answering questions — THIS would be a low quality website. Linking to this kind of site, especially if you do it repeatedly, may signal to Google that your site is not as high quality as it thought either if you’re endorsing junk.

However, a small website that’s creating useful content and just hasn’t gotten a big following yet is a different story. Feel free to link here and don’t feel pressured to only link to industry leaders just because they’re reputable.

Internal Linking Basics

Internal linking refers to links you use within your site that link to other content on your site. If I linked this sentence to another post I’d written a ways back that made sense contextually, that would be an internal link.

Other than the direct benefit of increasing readership within my site by giving readers more content to check out, internal linking is important for a few other reasons.

  1. Internal links can revitalize old content. Maybe you have an oldie but goodie, and maybe it got a good number of reads last year when you published, but the readership has died off. If it’s still relevant today, and topically makes sense in a current article that is getting attention, that link can infuse some attention and even increase the odds the old post ranks again on its own for awhile.
  2. These links show a relationship between pages/posts on your site. As Google crawls your website it’s trying to understand what your site is about, what each page is about, and how those pages relate to each other. You might have a core service page, and then several blog posts that explore different aspects of that service in ways the main service page doesn’t. If the core page linked to the blogs, or if the blogs linked back to the core page, it’d show Google that they are correlated versus all the other content on the site. That can clarify that topic and even improve topical rankings for those pages.
  3. Consistent internal linking can help establish a de-facto page for a given topic. As mentioned above, say you have several blog posts that explore different aspects of a topic you have a core page about. If each of those blog posts linked to that core page meaningfully somewhere in their content (with topical anchor text), it would start signalling to Google that that page is the go-to resource for that topic. Now, when it’s considering which page to rank for a related search query, it may look to that page first instead of other ‘competing’ content on your site.

Linking to your other content within reason is definitely something you should be doing if you blog regularly. It’s useful to readers and keeps more of your content in play at once without older stuff dropping off.

When Backlinks Can Get You Penalized

Even though building backlinks is important to any SEO campaign, you have to be careful. Like anything with SEO, strategies that are abused too often generally become dangerous.

Traditional “white hat” techniques are safer but time consuming to build. Any legitimate instance where someone else links to you meaningfully on a related topic is exactly what Google is looking for.

Examples of risky backlinks:

Links from private blog networks (PBNs). Essentially, these are groups of websites where users either pay to become a part of or just agree to it with the understanding that everyone will link to everyone else. Since these links are engineered and not truly because the users necessarily endorse each other’s content, Google considers this behavior spammy.

Other times, the way a PBN works is that users pay a fee to be able to post their content onto someone else’s blog. So rather than saying, “Here’s money, now link to me on your site,” it’s more like someone saying, “For a fee I’ll let you publish a post to my site with a link to yourself.”

Google is constantly scanning for this, making observations about the nature of the way sites link to each other.

While I’ll point out that SEOs I follow and trust do endorse PBNs, in some cases even swear by them, I’d say there’s a specific way you’d have to use them to “get away with it”. With the number of stories of people getting burned by them, it’s not something I generally recommend despite seeing skilled SEOs using them.

Paid links, such as those from Fiverr gigs, are also generally dangerous. This is because in order to attain the quantity of links most of these gigs promise — even at generous international currency exchange rates — sellers have to use spammy and automated methods.

This might mean software that creates spam blog comments across the web with your links in them, or creating mass numbers of junk profiles and dummy blog posts around the web simply for the sake of including your link. This is exactly the kind of thing Google is trying to stop, and when it starts seeing numbers of links pointing at your site from places like this it can decide to penalize your site.

As a related aside, I tested a number of the more legit-looking Fiverr gigs on myself last year for various keywords. In one notable case on a keyword I ranked #15 for and hoped backlinks would help get it in page 1, I instead found myself in position 56 shortly thereafter. The timing was perfectly aligned, and was a clear example of Google being onto what I tried and slapping the site for it. Glad I tried this on myself first before assigning it to clients.

This has unfortunately been consistent in my experience even with the most legit-looking Fiverr gigs by sellers claiming to have 10+ years experience in SEO, also claiming the gig is Penguin and Panda safe.

Social bookmarking is another method I’ve found to be risky. If you’re not familiar, social bookmarking sites allow you to create a free account and publicly share bookmarks to site you enjoy. The idea is supposed to encourage people to share information with each other.

Unfortunately, the bulk of people that ever used social bookmarking sites used them to create massive lists of backlinks to their own content. I don’t have a comprehensive list of which social bookmarking sites are safe and which are flagged as spammy, but I’d say as a general rule that even if listing your links on one of these sites doesn’t get you penalized, it’s also unlikely to help you much.

Article marketing sites like ezines and many others were abused so badly for backlinks that I wouldn’t advise anyone spend time there. The obvious exception of course would be that you don’t have a blog and want to establish yourself as an expert in a given field; publishing repeatedly those places can be useful.

But for everyone else that ever thought, “Hey, I could write a bunch of fast articles on this site and link to myself on each one and rack up backlinks fast!” Google is onto you.

One type of risky link that may surprise you is the footer link. Years ago this was all the rage, especially for web designers who wanted to put a “Site Built By XYZ Web Design Company” in the footer with a backlink to themselves. Or worse yet, fill a footer with topic links to a bunch of junk pages of different cities they wanted to rank in etc.

At best, these will do basically nothing for you because Google largely ignores them. But if links like this pointing at your site happen too often, you could be inviting a penalty.

An easy way to avoid the risk if you still want credit in the footer of a website is to include a rel=”nofollow” tag in the link. This allows users to follow the link and see who built someone’s site, but tells search engines not to consider the link.

Low quality PR and news syndication sites are another area that used to work great until they were abused mercilessly. Legitimate news sites have strict guidelines on fact-checking and substance within submitted pieces. Lower quality ones will accept and post almost anything.

At one time Google considered all news sites as authorities, so backlinks from these sites were significant. That is, until half the internet spammed these syndication networks with junk, got some quick rewards, and spurred Google to make some changes.