What is SEO and how does Google work? What decides who shows up first

SEO (search engine optimization) is the work of helping Google understand your website so it shows it to people looking for what you sell, without paying for ads. Google works in three stages: it crawls the web to find pages, indexes them (reads them and files them in its catalog) and, when someone searches, ranks them to decide the order. SEO makes sure your page gets through all three.

What decides who comes first isn’t a trick. According to Google, what matters most is helpful, reliable content, links from other sites and a page that works well on a phone. Changes can take anywhere from hours to several months to show, nobody can guarantee you the top spot, and you can do the basics yourself with two free Google tools.

What is SEO?

SEO, short for search engine optimization, is the set of changes that help search engines understand your content and help people find it. That’s how Google’s SEO Starter Guide defines it. It deals with organic results: the ones nobody pays to appear in.

The ads at the top marked “Sponsored” are a different thing: you pay per click through Google Ads, and they disappear when you stop paying. Paying for ads doesn’t lift you in the organic results: Google states that it doesn’t accept payment to crawl a site more often or rank it higher.

How does Google search work?

Think of Google as the world’s biggest library with a very fast librarian. First the librarian tours every bookshop looking for new books, then reads them and writes a card for each one in the catalog, and when you ask a question, pulls from the shelf the books that answer it best. Those are the three stages Google describes on that same page: crawling, indexing and serving results.

The catalog is huge: according to Google, its index holds hundreds of billions of web pages and is well over 100,000,000 gigabytes in size. And Google itself warns that it doesn’t guarantee it will crawl, index or show any page, even one that follows all its rules.

Crawling: Google has to find your page

Google almost always reaches a new page through a link from one it already knows, so a site nobody links to can take a while to appear. A sitemap, a file listing your pages, helps, although Google points out it doesn’t guarantee every page gets crawled, and a well-linked site of about 500 pages or fewer may not need one. A robots.txt file tells the crawler which parts of the site to stay out of.

Indexing: Google has to understand your page

This is where Google reads the content and tags such as the title, the blue headline shown in the result. When it finds several near-identical pages, it picks one as the main version, the canonical, and the rest stay in its shadow.

Ranking: the order of the results

When someone searches, Google chooses from what’s indexed and puts it in order. The same search doesn’t return the same list for everyone: according to Google, information such as the searcher’s location, language and device plays a part. “Pizza” in Austin and in Denver brings up different results.

What Google reads on a website: our test

To see this in practice, on October 25, 2026 we used curl in the terminal to open the files a crawler reads on vertizeplus.com, our own site. They’re public: you can do the same with your website by typing yourdomain.com/robots.txt into your browser.

One detail trips up a lot of people: robots.txt doesn’t hide a page from Google. Google is explicit that it isn’t a way to keep a page out of its results; for that you use noindex or put the page behind a password. That’s why our drafts use noindex rather than a robots.txt block.

What decides who shows up first on Google?

Google doesn’t publish the formula, but it does document what it looks at. According to its guide to ranking systems, original, helpful content counts, so do the links between pages (PageRank is still part of it), and so does page experience. Relevance always comes first: the page has to answer what was searched.

• Helpful, reliable content. Google’s systems aim to prioritize helpful, reliable information made to benefit people. Of its experience, expertise, authoritativeness and trust criteria, trust matters most.
• Links from other sites. Google uses how pages link to each other to understand what they’re about and which ones are useful. In practice, what counts are earned links: a local paper or a supplier writing about you.
• Page experience. Loading fast, looking right on a phone, using HTTPS and not covering the content with pop-ups. Google makes clear it will still show the most relevant page even if its experience is poor: this breaks ties between equally helpful pages.

Some things barely count, however often you hear them. According to Google’s Starter Guide, the meta keywords tag isn’t used, content length alone doesn’t affect ranking, and keywords in a domain name have hardly any effect. If you’re choosing a domain, pick one that’s easy to remember; we explain how in domain vs hosting vs DNS.

What is local SEO?

Local SEO means getting your business to show up when people search nearby, such as “hardware store open now” or “dentist near me,” on Google Maps and in results with a map. What matters most there is your Google Business Profile, which is free, more than your website.

According to Google’s help center, local results depend on three things: relevance (how well your profile matches the search), distance and prominence (how well known the business is: reviews, links, mentions). And there’s no way to pay for a better local ranking. We walk through it in how to add your business to Google Maps.

How long does SEO take to work?

Months, not days. Google’s Starter Guide says some changes take effect in a few hours and others can take several months, because Google has to crawl the page again and reassess it. A brand-new site starts with no links pointing to it, so the crawler takes longer to find it in the first place.

That’s why Google, on its page “Do you need an SEO?”, suggests asking anyone you hire what results they expect and in what timeframe.

Which SEO promises are hype?

Google keeps a list of red flags for anyone hiring SEO help, and almost all of them sound like a great deal:

• “We guarantee you the #1 spot on Google.” Google says it bluntly on that same page: no one can guarantee a #1 ranking.
• “We’ll submit you to thousands of search engines” or “priority submit to Google.” Google tells you to be wary of both; there’s no paid shortcut into the index.
• Link packages. Buying or selling links to rank, or trading goods or services for them, is spam under Google’s policies.
• Hundreds of mass-produced pages, with AI or without, made only to catch searches: Google calls it scaled content abuse.

The risk isn’t only wasted money. If an SEO uses banned techniques, Google can push your site down in the results or, where there’s deception, remove it from the index entirely. The penalty lands on your domain, not the agency’s.

What changes with Google’s AI Overviews?

For many searches, Google now answers at the top with an AI-written summary (AI Overviews) and also offers a chat-style AI Mode. According to Google, there are no extra requirements to be cited in them: the page has to be indexed and eligible to show with a snippet. In other words, the same SEO as always.

What can change is the number of clicks: if the summary already answers, someone after a quick fact may not visit. The summaries link to the pages they draw on, and those visits are counted in Search Console under the “Web” search type. Be wary of anyone selling “AI optimization” as something separate, with special files or markup: Google says none is needed.

What can you do for free on your own?

The basics don’t require hiring anyone. In this order:

1. Check whether you’re on Google. Search for site:yourdomain.com. If your pages show up, they’re in the index, as the Starter Guide explains.
2. Open Google Search Console, a free Google service. Verify your site and submit your sitemap; under Performance you’ll see which searches you appear for, how often and how many clicks you get.
3. Use URL Inspection in Search Console to see whether a page is indexed and, if it’s new, click Request indexing.
4. Create or complete your Google Business Profile: category, hours, photos and replies to reviews.
5. Write each page around a real question your customers ask, with a clear, unique title. “Banner printing prices in Tulsa” tells Google more than “Home.”
6. Check your site on your phone: it should load quickly and be readable without zooming.

The bottom line

SEO is getting Google to find, understand and choose your page, and it can’t be bought: it’s earned with helpful content, a site that works well and time. Start today with Search Console and your Business Profile, and be wary of any guaranteed top spot.

If what’s missing is the website itself, at Vertize Plus Business we build business websites that load fast, use HTTPS and are structured so Google can read them. We don’t promise rankings, because no one can.

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