What Is SEO? A Straight Answer, and the Full Map

Google “what is SEO” today and you’ll get three different answers depending on which corner of the internet you land in. One site tells you it’s technical, on-page, and off-page – full stop, textbook definition, moving on. Another tells you that’s outdated, that you now need GEO for AI search and AEO for answer engines, three separate disciplines with three separate playbooks. A third tries to split the difference and gives you a glossary entry with links to six other glossary entries.

None of them are lying to you. They’re just each holding one piece of something that stopped being simple a while ago.

Here’s my answer, the one I’d give you at a coffee shop instead of in a pitch deck: SEO is optimizing your page, your content, your app – whatever you’ve built – so the systems people use to find things can find it, and so the people on the other end of that search actually get what they came for. Google, Bing, ChatGPT, Perplexity, the app store search bar, YouTube’s algorithm. All of it. I call it search everywhere optimization, because that’s closer to how people actually search now than any of the three-letter acronyms floating around.

What SEO Actually Is

Fifteen years in, here’s what I’ve stopped believing needs a subcategory: getting found and getting understood are the same job, whichever engine is doing the reading.

Search Engine Land calls this “search everywhere optimization” too, in their own guide to the topic – it’s not just my framing, it’s a name the industry is groping toward because the old one stopped covering the territory. A person shopping for running shoes might start on TikTok, get a brand recommendation from ChatGPT, then type that brand into Google to check reviews before buying. That’s one search journey across three platforms. Treating it as three separate optimization problems – one for TikTok, one for AI answers, one for Google – misses that every one of those touchpoints is being shaped by the same underlying work: is your information structured so a machine can parse it, and does it actually solve the problem the person showed up with?

That’s the sentence I want you to leave with if you read nothing else here: SEO isn’t dying, and it isn’t being replaced by GEO or AEO. It’s the same discipline, doing more jobs than it used to, because the places people search multiplied and the work compounds across all of them.

How Search Engines (and AI Engines) Actually Find and Rank Things?

Strip away the jargon and every search system – Google, Bing, ChatGPT’s retrieval layer – runs the same three-step process underneath.

Crawling. A bot visits your site and follows the links it finds, the same way you’d follow a trail of breadcrumbs. If your site’s structure doesn’t give it a clear trail, whole sections of your content might as well not exist.

Indexing. Whatever the crawler found gets logged in a database, alongside what the content is actually about.

Ranking. When someone searches, an algorithm sorts through everything in the index and decides what to show, in what order, based on relevance and a few hundred other signals nobody outside Google has the full list of.

The part people miss with AI search specifically: Ahrefs’ own research on ChatGPT citations found that 88% of the URLs ChatGPT cites come from its underlying general search index – meaning the content still has to earn a place in a traditional search index before an AI assistant will ever mention it. Answer engines aren’t a parallel universe. They’re mostly reading off the same map, then summarizing what they find.

The Three-Part Map: Technical, On-Page, Off-Page

Ten years in, this part of the map hasn’t moved. What’s changed is what falls under each heading.

Technical SEO

Can the machines – search engines and AI crawlers both – actually get into your site and make sense of it? Site architecture, crawlability, page speed, and now: whether you’ve got an llms.txt file and markdown-friendly formats sitting alongside your regular HTML, because AI crawlers increasingly prefer to ingest a clean, structured version of your content rather than parsing a page full of navigation and ads.

I had a SaaS client whose product was genuinely good, but the site had no real structure behind it. Content wasn’t organized into anything resembling clusters, and the internal linking was close to non-existent – pages just floated, disconnected from each other. We went cluster by cluster: full technical audit first, then systematically optimized every page’s on-page elements, then built out internal linking properly – navigation, in-body links, the works. That systematic approach – fix the foundation, then link it together – got them a 190% increase in site traffic. Not from one clever trick. From doing the boring structural work properly and in sequence.

On-Page SEO

The page itself: layout, keyword usage, internal links, and whether someone reading it actually gets an answer that makes sense. I worked with an HR company once whose site was performing well, but their blog section was a mess – a glossary and articles all jumbled together with no real hierarchy, so the blog homepage read like a dumped list of links rather than something a visitor could navigate. We restructured it properly, and it had a real, measurable positive impact on their SEO. Nobody wants to read a glossary that looks like a junk drawer, and neither does a crawler trying to understand what the page is for.

Off-Page SEO

What happens away from your site: backlinks, brand mentions, whether your content gets shared or cited elsewhere. If ten years ago the industry was obsessed with backlinks almost to the exclusion of everything else, the correction I’d make for anyone starting today is: internal linking is the boring cousin nobody wants to work on, and it’s one of the most consequential things you can actually control yourself. Backlinks depend on someone else deciding to link to you. Internal linking depends on you deciding to do the work.

Where GEO and AEO Actually Fit

Here’s where I think the industry overcomplicates things, and where I want to be specific rather than vague about it.

GEO and AEO aren’t a fourth pillar bolted onto the three above. They’re the same three pillars, doing an additional job. Technical SEO already covered “can the machine read this” – now that includes llms.txt files and markdown formats for LLMs, alongside the traditional crawl signals. On-page SEO already covered “does this page make sense to a reader” – now that includes modular structure, tables, and shorter, more scannable sections, because AI engines are looking for concise, extractable answers just as much as human readers are. Off-page already covered “does the wider internet vouch for this” – now that includes whether your brand shows up consistently across the third-party content an AI assistant might draw from when it’s deciding who to cite.

Splitting these into separate disciplines with separate tactics misses that the work compounds. A well-structured, table-heavy, clearly-headed article helps a human skim it and helps an AI system extract an answer from it. It’s not two jobs. It’s one job that happens to serve two audiences at once.

Where I’d push back on some of the current GEO advice: there’s a real push toward heavy entity density and rigidly declarative language, and Kevin Indig’s research (cited via Ahrefs) found that heavily-cited AI content runs at roughly 20% entity density against 5-8% in standard prose, and uses definitive phrasing like “is defined as” nearly twice as often as content that doesn’t get cited. That’s real signal. But I’ve also seen a counter-example float through the industry – a small test where stacking in more stats, quotes, and confident tone actually dropped one page’s citation rate on a specific model. I don’t think that cancels out the entity-density finding. I think it’s a warning against treating entities as a checkbox instead of a structure.

Take Nike. Nike is an entity. Running shoes is a related entity. Usain Bolt, as a brand ambassador, is another entity, and the relationship between them – Bolt endorses Nike, Nike makes a specific shoe he’s associated with – is what an AI system is trying to map when it decides what to cite for a “best running shoes” query. You don’t need to force that relationship into a single sentence like a court deposition. You need it to exist naturally across your site and in how other people talk about your brand. Force it, and you’ve built something that reads like keyword stuffing wearing a new outfit. AI engines might still parse it. Google won’t reward it, and your actual readers will feel the seams.

How We Got Here

None of this appeared overnight. SEO has gone through PageRank, the Panda and Penguin quality crackdowns, mobile-first indexing, and now the shift toward AI-mediated search – each one forcing a genuine rebuild of what “doing SEO well” actually meant at the time. I’ve written the fuller version of that story, three decades condensed into the moments that actually mattered, in The History of SEO – worth reading if you want the “why” behind why the three-part map keeps holding even as the tactics inside it change.

The Specialisms

Once you’ve got the three-part map down, SEO branches into specialisms depending on what you’re optimizing for:

• Local SEO – visibility in map packs and location-based results, built around your Google Business Profile, reviews, and local citations.
• Ecommerce SEO – category and product page structure, faceted navigation, and the internal linking patterns specific to a storefront.
• Enterprise SEO – the same fundamentals at a scale where a single change might touch a million pages and three teams need to sign off before it ships.
• Technical SEO audits – a dedicated, periodic deep-dive into crawlability, indexation, and site health, distinct from the ongoing technical work described above.

And then there’s the layer this whole article has been circling: Generative Engine Optimization, Answer Engine Optimization, and what I’d call practical LLM SEO – each one a deeper look at a specific slice of the AI-search extension to the three-part map. If you want the technical mechanics of getting cited directly inside a ChatGPT response, that’s covered in my guide to ChatGPT citations. If you’re trying to understand where AI Overviews specifically fit into this, I’ve written that up separately too: how to actually show up in AI Overviews.

What SEO Actually Costs

SEO doesn’t cost you money to rank – nobody’s paying Google per click for an organic result. But it costs time, and time has a value whether you’re the one spending it or you’re paying someone else to.

If you’re doing it yourself, work out your own hourly rate and be honest about how many hours a proper technical audit, a content rebuild, and an ongoing cadence of internal linking and iteration actually take. If you’re hiring an agency or a freelancer, you’re paying for hours – ours typically run in blocks of ten, twenty, thirty, forty hours depending on the scope, plus the strategy and oversight wrapped around that time. Compared to paid search, where you’re buying clicks directly and the traffic stops the day you stop paying, SEO is slower to compound but tends to keep paying out well after the active work slows down. Calling it free is a bit of a misnomer. Calling it a long-term investment with a real, calculable cost is closer to accurate.

How I Actually Do SEO

My process, stripped down: I start by understanding what problem the business or the piece of content is actually trying to solve, and who it’s trying to solve it for. Then I look at the real search results – type the target term into Google myself, see who’s actually ranking, and work out what they’re doing well.

From there it’s gap analysis. What’s missing that I can add – a stronger internal linking structure, a section the top results gloss over, more backlinks pointing at a page that deserves them. I lean on Search Console to find pages losing ground or sitting just outside the top results, because a page that moves from position 11 to position 6 is often an easier, faster win than trying to build something from zero. Pull the keywords driving that page’s traffic, check the SERP for those terms in Ahrefs, do the same gap analysis, optimize, and push it back out. Then you iterate. SEO isn’t a project with an end date – it’s a loop you keep refining as the data tells you what’s working.

One thing that’s shifted in how I think about keywords specifically: it used to be about a target term and its long-tail variations – running shoes, buy running shoes, best running shoes for winter. Now I think in topics first, and the intent behind each variation matters more than the search volume attached to it. A lower-volume, high-intent term that gets someone to actually book, buy, or act is worth more to most businesses than a high-volume term that just gets someone browsing.

How to Spot Bad SEO Advice

If you’re a founder trying to hire someone, or you’ve already got someone and you’re not sure they’re any good, here’s what I’d tell you to check for.

Anyone promising a guaranteed ranking – a specific position, on a specific date – is telling you something no honest SEO can promise, because none of us control the algorithm. We can commit to the work and to trying. We can’t guarantee the outcome, because it isn’t entirely in our hands.

Watch the language in your reporting. If every update is “it’s coming, it’s coming, it’s coming” with no real explanation of what’s actually being done or why results haven’t shown yet, that’s a red flag. Good SEO reporting shows you the work, the reasoning, and an honest account of what’s working and what isn’t – not just reassurance. There’s a habit in this industry of leaning on heavy jargon to make simple things sound complicated, mostly so nobody asks a follow-up question. If an explanation makes you feel less informed than before you asked, that’s usually not because the topic is genuinely that complex.

Where This Goes Next

The three-part map isn’t going anywhere. What’s still shifting is what falls inside it – more markdown, more llms.txt files, more modular content built to be extracted by a machine as easily as it’s read by a person, more weight on genuine brand mentions across the web rather than just backlinks pointing at your own domain. None of that is a new discipline. It’s the same job, adjusting to more places search now happens.

FAQ

Is SEO dead now that people use ChatGPT and AI Overviews to search? No. Most AI citations still draw from the same underlying search index that traditional SEO targets – Ahrefs found 88% of ChatGPT’s cited URLs come from its general search index. Ranking well in traditional search remains the foundation AI visibility is built on top of.

Do I need a separate strategy for GEO or AEO, on top of my SEO strategy? Not a separate one – an extension of the same one. The structural and content-quality work that helps a page rank well in Google also tends to make it easier for an AI system to extract and cite. Treat GEO and AEO as additional considerations layered onto solid SEO, not a parallel workstream.

Can I do SEO myself, or do I need to hire someone? You can, particularly for a small site, if you’re willing to invest the time to learn keyword research, on-page structure, and basic technical health. Larger or more competitive sites usually benefit from someone who does this daily, simply because the gap analysis and iteration cycle gets more complex at scale.

How long does SEO take to show results? Most SEO work takes a few months before you see meaningful movement, and results tend to compound rather than spike. If someone’s promising fast, dramatic results, ask exactly what they’re doing to get there – some fast wins are legitimate optimization, and some are the kind of shortcut Google eventually penalizes.

What’s the difference between SEO and SEM? SEM (search engine marketing) is the umbrella term covering both SEO and paid search (PPC). SEO is the organic side – work that earns visibility without paying per click. PPC is the paid side, where you bid for placement and pay when someone clicks.

What are SEO keywords, and are they still relevant? Keywords are the terms and phrases people actually type or speak when searching for something. They’re still relevant, but the framing has shifted from isolated keyword lists toward topics and the intent behind each variation – what the searcher actually wants to do next matters more than the raw search volume of the term they used to get there.

How much does SEO actually cost? There’s no fee to rank organically, but SEO costs time – yours if you do it yourself, or an agency’s or freelancer’s hours if you hire out. Agency work is typically billed in blocks of hours; freelancers and consultants bill similarly. Weigh the hourly cost against the compounding, longer-term traffic SEO tends to generate versus the traffic that stops the moment you stop paying for ads.