Search engines work in three steps. First they crawl the web, sending automated programs to find pages by following links. Then they index what they find, storing and organizing it in a huge database. Finally, when someone searches, they rank the pages in that index and show the ones they judge most useful, in a fraction of a second. Everything in SEO comes back to those three steps: can Google find your pages, does it understand them, and does it trust them enough to show them.
This guide walks through each step in plain English, with a bit of history, and what it all means if you run a local business. We do SEO for contractors, so we will tie it back to that where it helps.
A short history
Early search engines in the 1990s mostly matched the words you typed to the words on a page. That made them easy to fool: stuff a page with a word enough times and it would rank.
In 1996, two Stanford graduate students, Larry Page and Sergey Brin, started a project called BackRub. Their idea was to judge a page partly by the links pointing to it. A link from one site to another worked like a vote, and votes from important sites counted more. They called the scoring system PageRank, and in 1998 they founded Google around it.
Links still matter today, but Google now weighs a huge number of other signals, from how well a page answers the question to how fast it loads on a phone. The basic three-step process has stayed the same.
Step 1: Crawling
Search engines use programs called crawlers, or spiders, to discover pages. Google’s is called Googlebot. A crawler starts with pages it already knows, follows the links on them to find new pages, and keeps going. It also reads sitemaps, which are files that list the pages a site wants found.
If no links point to a page and it is not in a sitemap, a crawler may never find it. Site owners can also tell crawlers to stay out of certain areas with a file called robots.txt.
What it means for you: every important page on your website should be linked from somewhere else on your site, and your site should have a sitemap. A service page that nothing links to is close to invisible.
Step 2: Indexing
Once a page is crawled, the search engine tries to understand it. It reads the text, the headings, the page title, image descriptions, and other signals, then stores the page in its index with notes about what it covers.
Not every crawled page gets indexed. Google may skip pages it sees as duplicates, very thin, or low value. That is why a site with fifty near-identical pages that only swap the city name often ends up with most of them left out.
What it means for you: each page should be about one clear thing, like one service, with enough real detail that it is worth storing. You can see which of your pages Google has indexed in Google Search Console.
Step 3: Ranking
When someone searches, the search engine pulls every page in its index that might match, then orders them. It tries to work out what the person actually wants, and which pages best deliver it. Signals it weighs include how relevant the page is to the search, how trustworthy the site is, whether other sites link to it, how well it works on a phone, and where the person is searching from.
That last one matters a lot for local businesses. Search “plumber” in Vancouver, WA, and you will see different results than someone searching the same word in Portland.
What it means for you: ranking is earned by being the most useful, most trusted answer for a specific search. A page that clearly explains one service in one area, on a site with good reviews and a few real local links, beats a vague page on a site nobody has heard of.
Local search works a little differently
For searches like “electrician near me,” Google also shows a map with three businesses, called the 3-pack. Those results come from Google Business Profiles, not just websites, and Google says they are based mainly on relevance, distance, and prominence. We explain that system in what the Google 3-pack is and how to get in it.
What about AI answers?
Search is changing. Google now shows AI-written summaries at the top of many results, and tools like ChatGPT answer questions directly and cite sources. Those systems still depend on crawled and indexed web pages. The pages they cite tend to be the ones that give a clear, direct answer early and back it up with specifics. Writing that way helps you in regular results too.
The short version for business owners
- Be findable: link every important page, and submit a sitemap.
- Be understandable: one clear topic per page, with a clear title and real detail.
- Be trusted: earn reviews, local links, and mentions over time.
- Be useful: answer the question the searcher actually has, quickly.
If you want to know whether Google is finding, indexing, and ranking your site the way it should, start with a free local search review. We will show you what is working, what is not, and why.