What is a backlink?

A link that is inbound to a webpage from an external and independent webpage. The amount and quality of backlinks a site has will influence its search ranking.

What Are Backlinks and How Do They Affect SEO?

A backlink, also known as an “inbound” or “incoming” link, is a link to one webpage from another. For example, if webpage A adds a hyperlink which leads to webpage B, that is a backlink for webpage B. Links, in general, are extremely important in the realm of SEO (search engine optimization)

The backlinks for a page are often described as “votes of confidence.” This is perhaps too clean-cut of an analogy. Not every backlink is equal, and it’s not just a race to get the most backlinks as fast as you can. The authority of the other webpages that are linking to yours, contextual relevance, and many other factors all affect how much authority the links pass on. 

Links are less like ballots in a box, and more like people pointing and saying, “listen to them.” You’ll be more likely to take the advice from a handful of people you trust, rather than many people who seem a little fishy. Additionally, if your content is bad, backlinks might prop you up in the short-term, but they aren’t a substitute for quality content.

The Google Algorithm

SEO strategy is based on search engine algorithms; more specifically, how they determine the trustworthiness of a website. Consider the old adage, “it’s not what you know, it’s who you know.” In terms of SEO, it’s actually both. What you know is the more important of the two. Bad content with a lot of backlinks is essentially a nice-looking house without support beams; its longevity is seriously compromised. However, who you know — or rather, who knows you — is extremely helpful in terms of getting good content some visibility. 

Backlinks can’t make up for bad content, but they can get more traffic for good content. An often overlooked fact is that webpages that provide a great answer to a user’s search can, and often do, outrank webpages with more backlinks that aren’t as user-friendly.  

Another important factor to consider is the Google algorithm, and particularly what we don’t know about it. The finer details of Google’s ranking algorithm are not publicly available information. Much of SEO strategy is based on what has been observed about rankings as a result of trial-and-error. We know backlinks are important, but some of the nuances are more opaque. 

External vs. Internal Links

An external link is a link between webpages on different domains, while an internal link is a link between pages on the same domain. External and internal links are both valuable to the user in terms of providing additional information and resources, but they serve different (to a degree) purposes in terms of ranking factors. An external link to a page passes some of the authority between the pages, whereas an internal link ties pages on the same site together — such that if one goes up in ranking, it will improve the status of the other as well. 

“Do-Follow” vs. “No-Follow” Links

“Do-follow” is a term that is not often used, and is essentially just the normal state of a link. The term mostly exists to be the antithesis of “no-follow.” “No-following” (often written as “nofollow,” mirroring how the attribute is expressed in HTML) a link is the process of indicating to search engine spiders that they should not follow a link. In theory, it should stop authority from being passed between the two pages.

The practice of no-following links — particularly blanket no-following links — has become controversial in recent years. The original purpose of the no-follow option was to counteract spam within online boards; people would post links to their websites on forums and boards in order to gain authority for their site — potentially damaging the authority of the board or forum in the process, by association. However, blanket no-following became arguably overused (due to websites using it in lieu of ensuring links on their web pages were reputable). As a result, the algorithm may have been altered to account for this problem.

In fact, a 2019 update from Google intends to add alternatives to “no-follow” in order to give site owners options other than blanket no-following. These are rel=“sponsored” and rel=“ugc”. The former identifies a link as a sponsor, and the latter identifies a link as user-generated content such as comments. Additionally, this update will identify all three designations as “hints” that the links should not be followed, rather than a strict blockade. This is intended to mitigate negative effects on web crawling, while also still allowing site owners to have some direct control over which sites they are associated with.

Since no-following has become more widely used, it is unclear exactly how effective no-following a link actually is, due to adjustments to the algorithm on Google’s part. However, generally speaking, outside of large forums that can’t feasibly be edited, like 4chan, good vetting and editing practices are usually more effective than no-following. A web page that is not open for public posting does not generally need to worry about links to spam web pages if they are doing the work in terms of citing sources well and/or contracting reliable writers.

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Link Building Guide

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Strategies to Create and Receive Quality Backlinks

Through trial-and-error (and what Google has divulged about the algorithm), there are some “rules” about linking which are relatively clear. Because Google’s self-stated goal is to provide users with a good, relevant answer to their queries, these “rules” all come back to making a page helpful and user-friendly. 

Examples of Good and Bad Backlinks

First and foremost, a linked page should match the anchor text (or AT) that it is attached to, and it should be very contextually relevant. Because the purpose of a link, from a user standpoint, is to provide additional information or citation if they would like to view it, a linked page should fit in with the context. For example, imagine a statement on a webpage that reads: “A zombie outbreak in the Australian Outback would be easily contained due to the unforgiving terrain and dangerous fauna found in the area.” A link within this statement to an article about tips for geriatric jazzercise would obviously not be relevant to the context. 

However, that is a bit of a dramatic example. An article about great hotels in Australia, insurance policies related to freak koala accidents, or the top 10 zombie movies of all time are also probably not contextually relevant enough to be linked to here. The keyword connection may be there, but it’s still too tenuous and isn’t giving more depth to the conversation so much as it is side-tracking to a tangential (at best) topic.

However, a link to a page about what the Australian Outback is, what kind of dangerous fauna and terrain there are in the area, or a top 10 list that ranks Australia highly for zombie apocalypse survivability are all potentially highly relevant and could be high-quality links. 

Additionally, the link should match the anchor text. Even if the link is contextually relevant, it will not be as valuable if it does not match the anchor text well. Let’s revisit our example, under the assumption that we have chosen to link to a Wikipedia page about the Australian Outback.

“A zombie outbreak in the Australian Outback would be easily contained due to the unforgiving terrain and dangerous fauna found in the area.”

“A zombie outbreak in the Australian Outback would be easily contained due to the unforgiving terrain and dangerous fauna found in the area. Learn more about the Australian Outback here.”

These are examples of poor use of anchor text. Even though the page is contextually relevant, the information on the page doesn’t have a strong relation to the actual words that it is attached to. In the second example, “white noise anchor text” is used, which, on its own, gives no contextual clues as to its destination. As such, white noise anchor text like “here,” “click here,” etc. should rarely, if ever, be used. Here is a much better example of anchor text for the given webpage:

“A zombie outbreak in the Australian Outback would be easily contained due to the unforgiving terrain and dangerous fauna found in the area.”

This anchor text closely matches the title and/or information on the webpage it is linking to. Due to the matching anchor text and relevance to the context, this is a quality link for the page it is on, and a quality backlink for the page it is linking to. 


A PBN (Private Blog Network) is, as the name implies, a network of blogs. These blogs work as a unit to link to each other and thus push each other higher in the rankings. This is generally considered a black hat tactic, because, as Google has improved its algorithm, it has gotten better at determining when a webpage is exploiting a loophole against the interest of the users. Things like sudden upsurges in popularity, many external backlinks from the same domain, and a concentrated amount backlinks from domains with a certain level of authority, can all be red flags for the algorithm. Additionally, skimping on the content in favor of exploiting loopholes will often lead only to short-term success, if any.

It may seem like, short of black hat strategies, the amount and quality of your backlinks are out of your control. However, there are ethical ways to improve your backlink profile, such as writing good quality content people will want to link to, writing for a domain with great authority, or reaching out to people who have mentioned you, or could benefit from mentioning you, in order to ask them for a link to your page.

How to Check a Backlink Profile

Although Google keeps the details of their algorithm under wraps, trying to build a solid backlink profile isn’t necessarily a blind endeavor where you throw some pennies in a well and hope for the best. Many websites offer tools that provide an overview of how many backlinks a given page has, along with approximations of how Google would evaluate said backlinks. In some cases, a webpage will not have a backlink profile, which is usually due to the page being very new or a lack of web visibility. 

Backlink analysis tools like Majestic will provide the user with a backlink profile that outlines the number, type, and general quality of backlinks on a page. This can help the user determine whether they are getting backlinks they want, or getting some they don’t want, such as spam pages. In the event of a backlink profile showing too many spam links, the webpage owner can ask the unwanted backlinking pages to remove the links, then show proof of this interaction to Google Support if refused. On the flip side, a user can improve their backlink profile by finding authoritative pages that mention the user’s web page directly, or discuss similar information, and ask the owner of the page to include a link. 

In short, backlink building to boost page authority and visibility can be done in both ethical and unethical ways. Doing so ethically and effectively is often largely just a matter of providing great content, citing sources correctly, and doing proper house-keeping on your website.