Link Building
A backlink is a link from one website to another. When a page on an external site links to a page on yours, it passes a signal of authority and relevance to Google. This is the mechanism behind PageRank - Google's original method for evaluating which pages deserve to rank. Decades later, with hundreds of additional ranking signals added, backlinks remain one of the strongest.
According to Backlinko's analysis of 11.8 million search results, pages ranking first on Google have 3.8 times more backlinks than pages ranking in positions 2 through 10. That gap does not happen by accident. Backlinks are one of the clearest measurable differences between pages that dominate competitive keywords and pages that do not.
Why backlinks still matter - and what has changed
Google has stated clearly that links remain a top-three ranking factor alongside content quality and relevance. What has changed is how Google evaluates them. Volume has given way to quality. A single link from a respected, relevant publication in your industry carries more weight than dozens of links from low-authority directories or unrelated sites. The shift has made link building both more valuable and more demanding - which is why 52.3% of digital marketers in an Editorial.link survey of 518 SEO experts ranked it as the most challenging aspect of SEO.
The competitive opportunity is significant. Backlinko's research found that 94% of all online content has zero external links. Most pages are competing without one of the strongest signals Google uses to assess authority. Earning even a modest number of high-quality links from relevant sources places a page ahead of the vast majority of the web.
What makes a backlink valuable
Not all links are equal. The factors that determine a link's value are relevance, authority, and placement. A link from a site in your industry, with genuine traffic and editorial standards, placed naturally within body content, carries substantially more weight than a link from an unrelated site added to a footer or directory listing. Google has become progressively better at identifying links that exist to manipulate rankings rather than to genuinely recommend content - and discounting or penalising them accordingly.
What this chapter covers
The four pages in this chapter cover link building from foundation to execution.
- Domain authority - how Google and third-party tools measure a site's link-based authority, what the metrics mean, and why the number of referring domains matters more than the raw number of backlinks.
- How to earn links - the content formats and strategies that attract backlinks naturally, including digital PR, original research, linkable assets, and the role of content depth in earning editorial links.
- Outreach - how to identify link prospects, what a strong outreach email looks like, and how to improve reply rates without resorting to the generic templates that fill most inboxes.
- Backlink audit - how to assess the quality of your existing link profile, identify toxic or low-quality links that may be harming performance, and use the disavow tool when necessary.
Next: Domain authority