Internal linking is linking from one page on your website to another. It is how Google discovers most of your pages, how it works out which ones you consider important, and how it learns what each page is about from the words used to link to it. It is also the one ranking lever that costs nothing and that you control completely.
Three jobs one link does
Discovery. Google says the vast majority of new pages it finds each day are found through links. A page that nothing links to depends on the sitemap, which is a weaker signal, and often ends up discovered but never crawled.
Priority. Pages linked from many places, and from important places such as the homepage and main navigation, are treated as more important. Pages buried five clicks deep behind a tag archive are treated accordingly.
Meaning. The anchor text of a link, the clickable words, tells Google what the destination is about before it gets there. Link to a page with the words quiet fireworks for weddings and you have described it. Link with read more and you have not.
Why small sites get this wrong
Because the website builder does it for them, badly. Automatic related-post widgets link by date or category, not by meaning. Navigation menus link to ten pages and leave the other fifty orphaned. Blog posts link out to sources and never to the site's own service pages, so the pages that sell get the least authority on the site.
The result is visible in Search Console. The homepage and a few navigation pages earn impressions; everything else is discovered and not indexed, or indexed and never shown.
A method that works
Every time you publish a page, add two links to it from existing pages that already get traffic, in the body text, using anchor text that names the topic. Every time you publish a page, link from it to the page you want the reader to reach next, and to the page that sells the relevant thing.
Order pages by difficulty and link along the chain. The easy explainer links to the harder comparison, which links to the service page. Each link carries context and a little authority in the direction of the money.
Once a quarter, list the pages that get impressions and the pages that do not, and add links from the first group to the second. It is the highest-return hour of SEO work most businesses never do.
What to avoid
Linking every keyword on every page to everything. Footer blocks of fifty keyword links. Identical anchor text for every link to a page. Links in places nobody clicks. Google reads all of it, but the patterns that look manufactured earn less than the ones that look like a person recommending the next thing to read.
Sources
Where this shows up in the tracker
Every term in this glossary is something the product actually measures or acts on. Plans start at £29 a month, with rank tracking, AI visibility, the daily AI readiness scan, security and domain health, Search Console, backlinks and audits on every one of them.
Related terms
Anchor text
Anchor text is the visible, clickable words of a link. Search engines read it as a description of the page being linked to, which makes it one of the clearest signals of what a page is about. Descriptive anchor text helps. Identical, keyword-stuffed anchor text across many links is one of the recognised marks of bought links.
Discovered, currently not indexed
Discovered, currently not indexed means Google knows a page exists, usually from your sitemap or a link, but has not yet fetched it. The page has not been judged and rejected. It has been queued and left there. On a small site that almost always means Google has not found a reason to prioritise it, not that your server is overloaded.
Topic cluster
A topic cluster is a set of pages that each answer one specific question about a subject, all linking to and from a central page that covers the subject as a whole. The central page is called a pillar or cornerstone page. The structure works because it concentrates internal links and relevance around one topic, which is how a site comes to rank for the whole of it rather than for scattered phrases.
PageRank
PageRank is the algorithm Google was founded on: a page's importance is estimated from the number and importance of the pages linking to it. Google still lists link analysis systems and PageRank among the systems it uses today. The public score was retired years ago, but the principle that links from trusted pages confer trust has never gone away.