What is SEO? The foundation under every AI-visibility play

What is search engine optimisation?

SEO is the practice of improving a site so that search engines can find it, understand it, and rank it well for relevant queries. It covers everything from how fast a page loads and how it is structured, through the words on the page, to the reputation the rest of the web lends it. The goal is durable: appear when someone searches for what you offer, and give them a reason to click.

Despite a decade of predictions to the contrary, SEO has not gone away. It has become the substrate. Answer engines and generative search still crawl, parse and weigh authority using machinery inherited from classic search. A site that is invisible to Google's crawler is usually invisible to the AI layer sitting on top of it.

SEO vs AEO vs GEO

Three acronyms, one continuum. Each optimises for a different surface, but they draw on a shared base of crawlability, structure and trust.

The three pillars of SEO

1. Technical SEO

The plumbing: crawlability, indexation, site speed, mobile rendering, structured data, a clean sitemap, and a robots.txt that permits the right bots. If crawlers cannot fetch and parse your pages, nothing else matters. This is also the pillar that most directly determines your AI visibility, because the same access and structure decide whether a model can read you.

2. On-page SEO

The content itself: relevant, specific pages with clear titles, sensible headings, and copy that answers what searchers actually want. This is where relevance is won or lost, and where generic marketing language quietly costs you both rankings and citations.

3. Off-page SEO

Everything that happens elsewhere: links, mentions, reviews and references that signal the wider web takes you seriously. Authority earned this way is slow and largely uncheatable, which is exactly why engines — classic and generative alike — weigh it heavily.

Why SEO is the foundation for AI visibility

Every AI-visibility technique assumes the SEO basics are in place. AI crawlers respect robots.txt, the same file classic crawlers do. Answer engines extract from semantic HTML, the same structure that helps you rank. Generative results favour authoritative entities, established by the same off-page signals that have always mattered. AEO and GEO are not a detour around SEO; they are what you build once SEO is holding weight.

This is also why a low AI-visibility score so often traces back to a technical SEO problem. A blocked crawler, a page rendered entirely in JavaScript, a missing sitemap — each one fails a human search engine and an answer engine at the same time. Fix the foundation and both surfaces improve together.

How to improve SEO performance

Phase 1 — Technical foundation

• Make sure every important page is crawlable, indexable and served in HTML the bot can parse without running your whole app.
• Fix Core Web Vitals — loading, interactivity and layout stability — because slow pages lose both rankings and visitors.
• Ship a valid sitemap and a deliberate robots.txt, and add structured data for the types you are.

Phase 2 — Content relevance

• Map the real queries your customers use and give each intent a page that answers it specifically.
• Write titles and headings that describe the content plainly, not cleverly.
• Replace generic claims with specifics — the details a competitor cannot paste onto their own site.

Phase 3 — Authority building

• Earn genuine links and mentions through work worth referencing, not through schemes engines are built to discount.
• Keep your entity details consistent everywhere so the knowledge graph resolves you cleanly.
• Maintain the pages that perform, rather than letting them rot into stale, distrusted URLs.

Frequently asked questions about SEO