How Google works
Crawling, rendering, indexing, ranking; the signals that matter and the myths.
Updated
What SEO is
SEO (Search Engine Optimization) = everything you do so that your pages show up as high as possible in Google results for relevant searches — without paying for ads. Organic traffic is free, steady and, for many sites, the biggest source of visitors.
SEO has three parts, each with its own lesson:
| Part | The question | Who does it |
|---|---|---|
| technical | can Google find, read and index the pages? | the developer — Technical SEO |
| content and keywords | do the pages answer what people search for? | content + the developer — Keywords |
| authority | do other sites trust you (links)? | marketing |
How Google works — 4 steps
crawlingGooglebot discovers and downloads pages→renderingruns the JS, sees the final page→indexinganalyzes the page and saves it in the index→rankingorders the results for a search1. Crawling — discovery
Googlebot starts from known pages and follows links. It finds new pages through: links on other pages (internal and external), the sitemap.xml, URLs submitted in Search Console. A page no link leads to (an orphan) is hard to find.
Crawl budget = how many pages Google is willing to crawl on your site. It matters for big sites (tens of thousands of pages): don't waste it on infinite filters, duplicates, internal search pages.
2. Rendering
Google runs JavaScript, but later and with limited resources. Content rendered on the server (SSR / SSG — see Rendering strategies) is seen immediately and reliably; content that only appears after client-side fetches can be delayed or missed.
3. Indexing
Google decides whether the page deserves a place in the index (the database the results come from). Not every discovered page gets indexed: thin, duplicate or noindex content stays out.
4. Ranking
For every search, Google orders the pages in the index by hundreds of signals. The most important ones, grouped:
| Group | Example signals |
|---|---|
| relevance | the page answers exactly the search intent; the terms appear in the title, headings, content |
| quality (E-E-A-T) | Experience, Expertise, Authoritativeness, Trust — a real author, sources, correct information |
| authority | links from other trustworthy sites (backlinks) |
| page experience | mobile, HTTPS, Core Web Vitals, no intrusive ads |
| freshness | for topics where it matters (news, prices, versions) |
What does not work (myths)
- Repeating the keyword 30 times (keyword stuffing) — penalized.
meta keywords— ignored by Google for over 15 years.- Bought links / link farms — penalized.
- Mass-generated content with no real value — filtered out by quality updates.
- "SEO is done once" — it's a continuous process: you measure, adjust, publish.
Summary
- SEO = technical + content + authority.
- Google: crawling → rendering → indexing → ranking; content rendered on the server is the safest.
- Ranking = relevance + quality + authority + experience; there are no tricks, only useful, accessible pages.