An internal link is a link from one page on your site to another. They are one of the few SEO levers entirely under your control — no other site has to agree, no tool is needed — and they do three separate jobs.
Crawlers find pages by following links. A page with no internal links pointing at it — an "orphan page" — is genuinely hard for a search engine to find, even if it is excellent. Every page worth indexing should be reachable by following links from somewhere.
Links tell search engines which pages relate to which. A guide about choosing a laptop that links to specific pages about processors and memory signals that those pages are part of a related cluster on the same subject. This helps engines understand the shape of your site, not just its individual pages.
When a page has value in a search engine's eyes, some of that value flows along the links it contains to the pages it points at. This is why a link from your homepage — usually your strongest page — carries more weight than one buried deep in an old post.
The practical use: if you have a page you want to perform better, link to it from your strongest, most-linked pages.
The clickable words in a link — the anchor text — tell both people and search engines what to expect on the other side.
<!-- Tells you nothing -->
<a href="/laptop-guide">Click here</a>
<a href="/laptop-guide">Read more</a>
<!-- Describes the destination -->
<a href="/laptop-guide">how to choose a student laptop</a>Write anchor text that would still make sense if read on its own, out of context. This is also an accessibility point — screen reader users can pull up a list of a page's links, and a list of twelve entries all reading "click here" is useless.
When you publish a new page, spend a moment adding links to it from existing relevant pages. This is the step most people skip — they link outward from the new page and never link inward to it, leaving it poorly connected from the start.