Backlinks: more than links, authority and reputation

Chapter 7 and last of the SEO from zero guide. Published in December 2019 and revised in August 2026. This revision corrects the definition: the original text said a backlink is a link you place pointing to another site, which is exactly backwards. We also added what was missing — link attributes, and what happens when links are bought.

We already know how a search engine works and, in the previous chapter, we learned to identify the terms that match a potential buyer’s intent. Now for what a backlink is, what it does, and how to earn one.

What is a backlink?

A backlink is a link another website places pointing at yours. Direction matters: a link going out from your site is an outbound link and it benefits the other party; the backlink is the one coming in.

Links you place between pages of your own site are internal links, and while they are not backlinks, they serve a different and equally important purpose. We get to them at the end of the chapter.

What are they for?

More people publish every day. So beyond examining your site’s content with its bots, a search engine leans on other signals to decide whether what you say is worth anything.

One of the oldest and sturdiest is exactly that: who links to you. A link is someone staking part of their reputation on you. When many trusted sites do it, you stop being just another domain and become a reference.

With one caveat the original version was missing: quantity does not count, provenance does. Ten links from recognised sites in your field are worth far more than a thousand from directories that link to everyone. And some links subtract: those from link farms or from sites built purely to link out are exactly what search engines have spent twenty years learning to spot.

How do you earn them?

The simplest approach is also the most honest: cite your sources. When you create content, link to what you used. And if it feels appropriate, write to whoever published it, tell them you cited them, and ask whether they would be interested in linking back. It does not always happen; when it does, it counts.

What works best over the medium term is duller and more effective: publish something worth citing. Original data, a guide that did not exist, a useful tool, a template. Nobody links to generic text; almost everybody links to something that saves them work.

Reasonable additions: being present in the directories and associations that actually matter in your field, contributing to trade publications, and showing up where your customers already look.

What not to do

Bought links — including sponsored articles that are not declared as such — breach Google’s spam policies. At best the link stops counting; at worst it drags the whole site down.

Mass link exchanges (“I link you, you link me” at scale) and signing comments on hundreds of blogs do not work any more either. They were effective fifteen years ago and today they are a cost with risk attached.

If for some reason you need to publish a link you do not want to endorse — advertising, third-party content, user comments — there is a correct way to do it: the rel="sponsored", rel="ugc" and rel="nofollow" attributes. They declare the nature of the link and stop it being read as a vote from you.

Internal linking: the part you control

Linking your own content together — exactly as we have done throughout this guide — does not carry the weight of an external vote, but it is the only part of all this that depends entirely on you. And it does three things:

• It helps crawling. Links are the search engine’s roads. A page with nothing internal pointing at it is a page that is hard to discover.
• It distributes authority. What arrives from outside onto your most-linked article can flow through to the pages you actually care about.
• It holds up navigation. Someone landing on a stray chapter who finds the previous one, the next one and the index will stay. Someone landing at a dead end leaves.

One tip about link text: describe the destination. “See [how a search engine works]” says far more than “click here”, both to the search engine and to anyone using a screen reader to jump from link to link.

End of the guide

That closes SEO from zero. If you have made it this far, you have what you need to hold an even conversation with anyone selling you search marketing — and, above all, to spot when you are being sold tricks from 2010.

The seven chapters boil down to one idea: understand what the person searching needs, answer them better than anyone else, and clear away everything that gets in their way. The rest is detail, even if some details take months.

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