Search engine optimisation: how it works, lever by lever

	Technical	Content	Links
The question	can Google read my pages?	do my pages answer the search?	do other sites mention me?
Where to check	Search Console	your pages, reread	links and reviews you receive

You’ve seen “search engine optimisation” on a quote or in an article, and you want to know what’s behind it. Here’s a working definition, how a search engine works, and the three levers you can pull. It’s part of our guide to SEO for small business.

The SemChat links on this page are affiliate links: if you subscribe through them, I earn a commission, at no extra cost to you and with no effect on what I write.

What is search engine optimisation? A working definition

Search engine optimisation is the work done on your site so a search engine understands it and shows it to the right people. Google’s definition: it “is about helping search engines understand your content, and helping users find your site” (SEO Starter Guide, read 30 October 2026). British English spells it “search engine optimisation”; it’s the same thing.

The short answer on the acronym

SEO stands for search engine optimisation. “SEO optimisation” and “SEO search engine optimisation” repeat the same word twice, but people search for them, so you’ll see them around.

SEO, search engine optimisation and search engine marketing

Search engine marketing (SEM) usually means paid search: ads on Google, billed per click. SEO works on organic results, which are free at Google. Ads stop when the budget stops; pages that rank keep bringing visits while they stay useful. Prices for both are on the SEO cost page.

How search engines work: crawl, index, rank

Google’s page on how Search works, in three stages. Screenshot of developers.google.com/search/docs/fundamentals/how-search-works, taken 30 October 2026.

In Google’s words: “Google Search works in three stages, and not all pages make it through each stage” (page read 30 October 2026).

1. Crawling: Googlebot downloads pages, mostly found by following links.
2. Indexing: Google analyses each page and stores it in its index.
3. Serving search results: for each search, it returns the pages it judges most useful.

And the warning that goes with it: “Google doesn’t guarantee that it will crawl, index, or serve your page”.

How search engines organise pages

The index works like a huge library catalogue. A page that isn’t in it can’t show up, however good it is. That’s why the first check is always “is my page indexed?”, in Search Console or with a site: search.

How Google decides the order

Google weighs many factors, including the user’s location, language and device (How Search works, read 30 October 2026). One thing it doesn’t weigh is money: “Google doesn’t accept payment to crawl a site more frequently, or rank it higher” (same page).

The ranking factors, in plain words

Google doesn’t publish a full list. What its documentation does say, in plain words:

• Relevance: does the page answer the search?
• Helpfulness and reliability: Google asks for helpful, reliable, people-first content.
• Page experience: Core Web Vitals “are used by our ranking systems”, but good scores don’t guarantee a top spot (Understanding page experience, read 30 October 2026).
• Context: where the person is, their language, their device.

What doesn’t count: the length of the content alone, according to Google’s SEO Starter Guide.

Lever one: technical, so Google can read your site

Pages that load, on HTTPS, readable on a phone, linked to each other. Google notes that “Most searches are now done from mobile devices” (How to get your website on Google, read 30 October 2026). A technical audit checks all this at once.

The key indicators of a real technical audit by SemChat, 29 October 2026 (French interface). Screenshot of the SemChat app, Jérémy’s account, Free plan.

On 29 October 2026, SemChat’s audit of my site plugkit-avis.com (run in French) returned a technical score of 99 out of 100 and 189 indexable pages, along with a contact page in 404 error that I confirmed by hand. A score is the tool’s own measure, not Google’s: what counts is whether your pages get indexed and shown.

Lever two: content that answers the search

One page per customer need, written with the words customers use. Answer the question in the first lines, then give the details: prices, area, photos, a way to reach you.

SEO optimisation: what it means for one page

An optimised page has a clear title that starts with the search it targets, a direct answer near the top, headings, described images, and links to related pages. Nothing hidden, nothing stuffed.

Lever three: links from other sites

Links from other sites: other people vouching for you. Illustration by Zéro Corvée.

Links from other sites help Google find your pages and show that others vouch for you. Earn them from your trade association, partners, suppliers, local press. Never buy them: “please don’t pay them to link to you; that could be considered a violation of Google’s spam policies” (How to get your website on Google, read 30 October 2026).

User experience: the thread through all three

1. 1 Technical the page opens fast, on any phone
2. 2 Content the visitor finds the answer right away
3. 3 Links satisfied people mention you elsewhere

Each lever serves the visitor first. A fast page that answers well gets read, shared and linked; Google’s systems try to reward that.

Common myths about search engine optimisation

Google’s own documentation clears up several ideas that still circulate on quotes and forums (SEO Starter Guide, read 30 October 2026):

• “Longer pages rank better.” Google states that the length of the content alone doesn’t matter for ranking. A short page that answers beats a long page that wanders.
• “Put the keyword in your domain name.” Google writes that keywords in a domain name alone have hardly any effect.
• “Fill in the keywords meta tag.” Google Search doesn’t use it.
• “E-E-A-T is a ranking factor you can tick.” Asked whether it is a ranking factor, Google answers: “No, it’s not.” Experience, expertise, authority and trust describe what helpful content looks like, not a box to fill.
• “Someone knows the secret.” Google’s guide says there are no secrets that will automatically rank a site first.

Search engine optimisation in practice: your first month

You don’t need a plan on paper. Four weeks, one block a week, is enough to start:

1. Week 1: be seen. Verify your site in Search Console. Open the Pages report and note how many pages are indexed and why others aren’t.
2. Week 2: fix what blocks. Repair or redirect pages in error, submit your sitemap, check that your site runs on HTTPS and reads well on a phone.
3. Week 3: improve one page. Pick the page that matters most for your business. Rewrite its title so it starts with the search you target, answer the question in the first lines, add photos with clear descriptions, link it from your home page.
4. Week 4: earn mentions. Ask three partners or suppliers for a link, and ask your last satisfied customers for a review on your Business Profile.

Then measure once a month in Search Console: impressions, clicks, indexed pages. Change one thing at a time so you know what worked.

How long search engine optimisation takes

There’s no fixed delay. Google writes that some changes take effect in a few hours while others can take several months, and suggests waiting a few weeks before judging a change (SEO Starter Guide, read 30 October 2026). A new page can take from a few days to a few weeks to be crawled, and requesting a crawl doesn’t guarantee inclusion at all (Ask Google to recrawl your URLs, same date). Plan in months; ads are the only instant option, and they stop with the budget.

Google and the other search engines

Google isn’t the only engine: Bing, for example, has its own tool for site owners, Bing Webmaster Tools. The three levers are the same everywhere. Market share figures for the US: missing data (planned source: a dated measurement of search engine market share).

Search engine optimisation techniques you can apply yourself

1. Verify your site in Search Console and check the Pages report.
2. Fix pages in error and submit your sitemap.
3. Rewrite the titles of pages with many impressions and few clicks.
4. Link your pages to each other with descriptive words.
5. Ask partners and customers for links and reviews, never paid.

The step-by-step guides: how to get my website on Google and how to improve SEO.

Free search engine optimisation tools to start with

Google’s Search Console overview page, a free tool. Screenshot of search.google.com/search-console/about, taken 30 October 2026.

Search Console is free, and PageSpeed Insights only needs your page’s address. SemChat’s Free plan costs €0, “Try semchat with no credit card” (semchat.io/en/pricing, read 30 October 2026); note that one full audit used up its whole monthly quota in my test. My full test is in the SemChat review.

A free search engine optimisation course

Google’s SEO Starter Guide is free and open to all, written for site owners rather than specialists. Read it once, then practice on your own site.

More on the basics: SEO meaning in plain words, how to get my website on Google for free for no-cost levers, and how to get to the top of Google search for ranking higher.

Search engine optimisation comes down to three levers: a site Google can read, pages that answer, links you earn. Check them in that order.