Part of the SEO from Scratch series
Most people use a search engine ten, twenty, fifty times a day without ever wondering what it is actually doing.
You type something into that little box. Half a second later, ten results appear. You click one, you find your answer, and you move on with your day.
But have you ever stopped to ask, properly, what just happened?
That tiny moment between you hitting Enter and the results appearing on your screen is one of the most extraordinary things humans have ever built. And it is also the entire reason a job called SEO exists.
This is the first post in the SEO from Scratch series. We are starting from zero. No jargon. No assumptions. No rush. Just a friendly walk through how all of this actually works, one idea at a time. By the end of the series, you will understand search engines well enough to talk about them with confidence, build a website that gets found by real people, or even start thinking about SEO as a career.
But today, we just want to answer one simple question.
What is a search engine actually doing when you search?
Why This Matters
If you have ever wanted your website, your business, your blog, or your product to be found online, this question is the doorway to everything else.
Every other concept in SEO, from keywords to backlinks to structured data, sits on top of one foundation: understanding what a search engine is actually doing under the bonnet.
Skip this and the rest will feel like scattered fragments. Understand this and the rest will click into place naturally.
Key Takeaways
- A search engine is not “the internet”. It is a tool that searches the internet for you.
- Search engines look at billions of pages and choose roughly ten to show you for each search.
- The order matters. The pages chosen first get most of the clicks. The rest get almost none.
- Google is the most popular search engine, but it is not the only one. Bing, DuckDuckGo, Yahoo, and newer AI-powered tools like Perplexity, ChatGPT search, and Google’s own AI Overviews all do similar work.
- The choices a search engine makes about what to show first are the reason a job called SEO exists.
The library that has no end
Imagine you walk into a library. The biggest library you can picture. Bigger than your town. Bigger than London. Bigger than the world. Stretching further than your eyes can see in every direction.
This library has billions of books. That is not an exaggeration. There are over a hundred billion pages of information online today, written by people from every corner of the planet, in every language, on every topic you can think of.
Now picture this. You walk up to the desk and say to the librarian, “I want to know how to cook jollof rice.”
The librarian disappears for less than a second. Then she comes back, carrying ten books, each one opened to exactly the right page, arranged in the order she thinks will help you most.
You did not see her run. You did not see her think. You did not see her flip through anything. She just appeared, with answers.
That is what a search engine is doing every single time you search.
The thing most people never notice
Here is the part that really matters.
The librarian could have brought you any books from that endless library. She had a hundred billion to choose from.
She chose ten.
And she did not just choose them at random. She put one at the top. One at number two. One at number three. All the way down to ten.
She made a decision. A very specific decision. About which ten, in what order.
And she does this for everyone. Every person who walks up to her desk. Every second of every day. All over the world. Billions of searches a day. Each one ending with ten chosen books in a chosen order.
Google is not the only librarian
Most people in the UK and most of the world use Google. Around nine out of every ten searches happen there. That is why we say “Googling” something rather than “searching”.
But Google is just one search engine. There are others. Bing, made by Microsoft, powers a lot of business searches and is becoming more important because of its connection to ChatGPT. DuckDuckGo is the one privacy-focused people use. Yahoo still exists. In other parts of the world, Baidu in China and Yandex in Russia are dominant.
And there is a newer kind of search engine now. The AI-powered ones. Tools like Perplexity, ChatGPT Search, Claude, and Google’s own AI Overviews do not just give you a list of links. They read across many pages and write you an answer in plain language, often citing the sources they used.
Different librarians. Same fundamental job. They are all looking at the enormous library of the internet, deciding which pages to bring you, and showing them to you in an order they have chosen.
For the rest of this series, when we say “search engine”, we mean all of them. Google will come up a lot because most readers use it, but the principles apply to every search engine, including the AI ones.
Why this matters more than you think
If you owned one of those billion books, you would really, really want to be one of the ten she picks.
Why? Because the people who walk in and ask her questions almost never look past those ten. They take what she gives them, say thank you, and walk out.
The books she does not pick? They stay on the shelf. Unopened. Unread. Even if they were brilliant. Even if they had the best answer in the entire library.
That is the world every website lives in. There are over a billion websites online today. When someone searches for what your site is about, the search engine picks ten. Either you are one of them, or you are not.
And if you are not, almost nobody finds you.
So the question becomes
How does she choose?
What is the librarian looking at when she decides which book goes first, which one goes second, and which one never gets picked up at all?
That is the question that opens the door to SEO. Once you understand how she chooses, everything else you read about search engines from now on will start to make sense.
Try this before you read the next post
Open any search engine on your phone. Type any question you have actually wondered about this week. A real question. Something you searched for recently or want to know more about.
Now look at the ten results that appear.
Ask yourself: out of all the websites in the world that probably wrote about this topic, why did the search engine pick these ten? Why this one first? Why is the one on page two not on page one?
You will not have an answer yet. That is fine. The point is just to start noticing that a choice is being made, right in front of you, every single time you search.
Common misconceptions
Before we move on, let us gently clear up a few of the most common misunderstandings about search engines. Most people arrive at SEO with at least one of these already in their head. Knowing they are wrong now will save you a lot of confusion later in the series.
“A search engine searches the internet in real time when I type.”
Not quite. The hard work was done long before you searched. Search engines visit and read pages in advance, store what they find, and then look up answers from that stored copy when you search. We will cover this properly in a later post.
“Google shows me everything written about my topic.”
No. It shows you what it decided to show you. Out of possibly millions of pages, you see ten on the first page. The rest are still out there. You just will not see them, because almost nobody clicks past the first page.
“If a website is good, it will rank automatically.”
No. Being good is necessary but not enough. Search engines have no way to “feel” that your site is good. They need signals they can read, which is exactly what SEO helps you give them.
“SEO is a trick to game the system.”
Modern SEO is the opposite. It is the practice of helping search engines accurately understand and recommend genuinely good sites.
Frequently asked questions
These are the questions beginners most often ask after reading a lesson like this one. Some of them may already be running through your head. The answers are short. Read whichever ones speak to you and skip the rest.
What is the difference between a search engine and a browser?
A browser, like Chrome, Safari, or Firefox, is the app you use to view websites. A search engine, like Google or Bing, is a service you visit through your browser to find websites. You can open a browser without using a search engine, but you usually use a search engine inside a browser.
Is Google the same as the internet?
No. The internet is the global network of connected websites and services. Google is one company that built a search engine to help you find things on that network. The internet existed before Google and would keep existing if Google disappeared tomorrow.
How many websites are on the internet?
Estimates vary, but there are over 1 billion registered domains worldwide, with a smaller number that are actually active and regularly updated. Search engines try to find and store information from as many useful ones as they can.
Do AI tools like ChatGPT count as search engines?
Yes and no. They are not traditional search engines, but the newer versions of these tools do search the internet, read across many pages, and give you answers. They are increasingly part of how people find information online, which is why understanding them matters for modern SEO.
Why do I get different results when I search the same thing on different days?
Because the librarian’s mind keeps changing. Search engines update what they know about the web every minute, and their rules for choosing results keep evolving. We will explore this in much more detail later in the series.
Key terms from this lesson
Click any term to read its full glossary post.
Search engine: A tool that searches through the internet and shows you a list of pages it thinks match your question.
SERP: Search Engine Results Page. The page of results you see after you type a search.
Internet: The global network of websites and services. The library, in our analogy.
SEO: Search Engine Optimisation. The practice of helping a website be one of the pages a search engine chooses to show.
What you learned today
A search engine is not showing you “the internet”. It is making a choice, on your behalf, out of an unimaginably huge library about which small handful of pages to put in front of you, in a specific order. That choice is the entire reason SEO exists.
That is enough for one lesson. Sit with it. The next one builds directly on it.
Test what you learned
Ready to lock this lesson into memory? Take the quiz for this post in the SEO from Scratch quiz section.
Up Next
In the next post, we open up the question we left hanging today.
How does a search engine actually choose those ten results? What is it looking at when it decides which website deserves to go first and which one stays buried on page eight?
We will meet the three things every search engine cares about most. They are simpler than you might expect, and they are the foundation that absolutely everything else in SEO sits on top of. Once you have these three, the rest of the series will feel like you are just connecting dots.
Up Next: How Does a Search Engine Choose Which Results to Show First? (link to be added once published)
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