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Google SEO Basics + How Search Works + Search Essentials

Entry-level guide to Google Search Central. Covers the 3 stages of Google Search (crawl/index/serve), the 3 pillars of Search Essentials (technical requirements/spam policies/best practices), E-E-A-T and helpful content self-checks, the impact of generative AI (AI Overviews + AI Mode) on SEO, things you don’t need to do (AEO/GEO/chunking/llms.txt are all myths), pitfalls to avoid when hiring an SEO consultant, and complete checklists for site launch, content optimization, links, mobile, and HTTPS.

Source collection：Google Search and SEO · Published here：2026-09-26 · Note updated：2026-09-26

SEOSearch EnginesOrganic growth

Consolidation of the entry-level layer of Google Search Central documentation (fundamentals/ + essentials/ + top-level navigation). Compiled from 14 English sources and 14 machine-translated zh-cn equivalents of the same sources.

This wiki is the entry point to the GSC knowledge base; for in-depth topics, see the related 13 sister wikis listed in.

1. The 3 stages of Google Search (crawling / indexing / serving)

Stage What it does When it can fail
Crawling Crawling Googlebot programmatically discovers URLs → visits and downloads page text, images, and videos Blocked by robots.txt / HTTP 5xx errors / login walls
Indexing Indexing Parses content, determines duplicate pages vs canonical pages (canonical), collects signals for language/region/usability, and stores pages in the Google index Low-quality content / noindex robots meta / JS rendering failures
Serving Serving When a user submits a query, returns the most relevant, highest-quality results based on hundreds of factors Content irrelevant to the query / noindex meta tags that prevent serving

Key invariants:

Why this matters: Most SEO problem diagnosis comes down to "which stage failed". The URL Inspection Tool in Search Console is the official tool for checking these 3 stages (for details, see How to Use the Search Console + Analytics + Trends Trio (Traffic Diagnostics / Keyword Research / Looker Studio)).

2. What SEO is, whether you need it, and who should do it

SEO = Search Engine Optimization, SEO is essentially helping search engines understand your content + helping users find you. SEO is not black magic to trick rankings; Google explicitly states "there are no secrets here that'll automatically rank your site first".

Step 0 after your site goes live: Confirm Google knows you exist

Check your own site using the site: operator:

site:example.com
  • Results appear → You are in the index, and you can start optimizing
  • No results → Check if technical requirements is passed and wait for natural discovery (new sites may take days to weeks)

When you don’t need professional SEO

  • Small local business + simple content + small site → Reading the fundamentals series yourself is enough
  • You already use a CMS (WordPress/Wix/Shopify) + default settings are basically fine
  • You can’t wait for results (SEO typically takes 4 months to 1 year to show results)

When to hire an SEO and how to choose one

Best time to hire:Before a site redesign or new site launch, so SEO can be involved at the architecture level. 5 steps to choose:

  1. Commit to actually implementing SEO recommendations — otherwise don’t hire, it’s a waste of money
  2. Interview — Ask about past cases, whether they follow Google Search Essentials, industry experience, communication style, and whether they will list all changes
  3. Check business references — Ask past clients if they were easy to work with and delivered positive results
  4. Pay for a technical + search audit — Give them read-only Search Console access.Do not give write access. The audit output must include "realistic improvement estimates + workload estimates". Anyone who "guarantees #1 ranking" is a scammer
  5. Decide whether to sign a contract

8 common scams in the SEO industry

Scam How to spot it
Shadow domain A domain owned by the SEO that redirects users to your site via deceptive redirects. If the partnership breaks down, they can point it to a competitor
Doorway page Intermediate pages stuffed with keywords that actually siphon link juice to the SEO’s other clients
Link scheme Buying/selling links / reciprocal linking / automated backlinks → Violates spam policy, may result in manual action
Guarantee #1 No one can guarantee Google rankings. Anyone who says this is 100% a scammer
Special relationship with Google Google does not sell any "special privileges"; this claim is also a scam
Priority submit This does not exist. There are only 3 submission methods: URL Inspection Tool / Sitemap / Indexing API (all done by you yourself)
Unsolicited email ("Your site is not indexed by search engines...") On the same level as "miracle weight loss pills" and "African prince wire transfers" — delete it directly
Pay-per-rank with hidden fee Putting you in ad slots instead of organic results. Ask clearly "which payment is for permanent inclusion vs temporary advertising"

Reporting: In the US, file with the FTC(ftc.gov); in other countries, file with econsumer.gov.

3. The three pillars of Search Essentials

Search Essentials is Google’s minimum set of requirements for whether to show you in Search, consisting of 3 pillars:

Technical requirements (3 items, met naturally by almost all sites)

  1. Googlebot is not blocked — Not disallowed in robots.txt, no login wall (for details, see Complete Guide to Crawling and Indexing Controls (robots.txt / noindex / X-Robots-Tag / data-nosnippet / rel))
  2. Pages work properly — Return HTTP 200 (success), not 4xx/5xx
  3. Pages have indexable content — Text is in Google-supported file types (HTML / PDF / images / videos / Office documents, etc.)

Important: Meeting these 3 requirements does not guarantee being indexed. Google also looks at quality, duplication, and whether spam policies are violated.

Spam policies (24 prohibitions; violations lead to demotion/removal)

For details, see §7 Full List of Spam Policies.

Key best practices (7 key best practices)

4. Technical preparation from a developer perspective (condensed from get-started-developers)

If you are a developer, build a search-friendly site for Google at the code level:

Checklist item How to do it
Does Google see the same page as users? URL Inspection Tool / Rich Results Test
Can all URLs be linked to? Use <a href> elements; one URL per piece of content; give each screen in an SPA a unique URL
Do you use JS? Follow JS SEO best practices (for details, see Complete JavaScript SEO Guide (Basics + Diagnostics + Dynamic Rendering + Lazy Loading))
Does Google know when content is updated? Submit a sitemap + use URL Inspection to request recrawling
Can Googlebot "see" the text? Visual content must have text equivalents (product image lists must have text descriptions); each page must have a descriptive title + meta description; use semantic HTML; content must be in the DOM (text inserted via the CSS content: property is not indexed)
Does Google know you have multiple versions (mobile/desktop/multilingual)? Consolidate duplicate URLs / use hreflang (for details, see Complete Guide to Canonicals / Redirects / Site Migrations (Including Full HTTP Status Code Table + 503 Temporary Outage Playbook) Complete Guide to Internationalization (hreflang/Multilingual/Multi-region) + Explicit Content (SafeSearch/Adult))
How to control what content Google does not see login wall / robots.txt / noindex meta tags (the three mechanisms each have applicable scenarios; for details, see Complete Guide to Crawling and Indexing Controls (robots.txt / noindex / X-Robots-Tag / data-nosnippet / rel))
How to enable rich results Add structured data (for details, see Complete Structured Data Overview (framework + one-click lookup for 34 rich result types + JSON-LD/Microdata/RDFa selection guide))

The most counterintuitive point: Google may not see what you think it sees. The most common reasons are:

  • Googlebot does not support JS-rendered content (old frameworks / asynchronous loading)
  • Resources (CSS/JS/images) are blocked by robots.txt → rendering fails → Google thinks the page is blank
  • CSS content: text inserted via the property is not in the DOM → not indexed

Run this every time you have doubts URL Inspection Tool → Live URL to see Google's actual view.

5. Helpful content & E-E-A-T self-check

Google's ranking systems reward helpful, reliable, people-first content. "Helpful content" is an abstract concept, and Google provides4 categories of self-check questions + 1 Who/How/Why framework:

Content quality self-check (11 questions)

  • Does it provide original information, reporting, research, or analysis?
  • Does it provide a complete, comprehensive description of the topic?
  • Does it provide insightful analysis beyond the obvious?
  • When citing other sources, does it avoid simply copying or rewriting, and add substantial original value?
  • Does the headline accurately describe the content, without exaggeration or clickbait?
  • Would you want to bookmark, share, or recommend this page?
  • Would you expect to see this content in a print magazine, encyclopedia, or book?
  • Compared to other pages in search results, does it provide substantial additional value?
  • Are there spelling errors or stylistic issues?
  • Does it look mass-produced or thrown together hastily?
  • Is it mass-produced or outsourced to a large network of creators (so that individual pages or sites do not get enough attention or polish)?

Expertise self-check (4 questions)

  • Does the way content is presented inspire trust (clear sources, professional evidence, author background, About page)?
  • If someone researched your site, would they consider it a widely recognized authority in the field?
  • Was the content written or reviewed by experts or experienced enthusiasts in that field?
  • Are there easily verifiable factual errors?

People-first (5 questions) — answering yes means you are on the right track

  • Is there an existing or target audience that would find the content useful if they came directly to your site?
  • Does the content clearly demonstrate first-hand expertise or deep knowledge(having used the product, visited the place)?
  • Does the site have a clear primary purpose or focus?
  • After reading, will a user feel they have learned enough and achieved their goal?
  • After reading, will a user feel satisfied?

Search-engine-first warning (13 questions) — answering yes means you are going in the wrong direction

  • Is the content primarily made to attract visits from search engines?
  • Are you producing large amounts of content across many topics,hoping some of it will rank well?
  • Are you using extensive automation to produce content on many topics?
  • Are you mainly summarizing what others have said without adding much value?
  • Are you writing about trending topics rather than for your existing audience?
  • Do readers have to search again to find better information?
  • Are you writing to a specific word count because "Google prefers X number of words"? (Google does not have an ideal word count)
  • Entering niches where you have no expertise just for traffic?
  • Promising an answer to a question that actually has no answer(such as an unconfirmed release date for a product)?
  • Making no substantial content changes but only changing dates to fake freshness?
  • Adding large amounts of new content or removing old content just to make the site "seem fresh"? (This does not work)

E-E-A-T framework (Experience / Expertise / Authoritativeness / Trustworthiness)

  • It is not a direct ranking factor — Google uses many signals to identify content that appears to have strong E-E-A-T content
  • Trust is the most important, and the other three are its pillars
  • YMYL(Your Money or Your Life) topics (health/finance/safety/well-being) are more sensitive to E-E-A-T, and Google applies heavier weighting
  • Quality raters use search quality rater guidelines to provide feedback,rater feedback does not directly enter the algorithm, but it helps Google validate algorithm performance

Who / How / Why framework (the most practical self-check)

Dimension What to ask Action
Who Who created it Can visitors tell who the author is at a glance? Is there a byline? Does the byline link to the author's introduction? Add accurate bylines + author bios + About page
How How it was made In product reviews: how many items were tested? What were the test results? What was the testing methodology? Is there photographic evidence? Is there transparent disclosure of automation/AI generation? Add disclosure in content where "How was this made?" is a reasonable question
Why Why it was written This is the most important. Is it to help people, or to trick search traffic? "Primarily to help people" is the right approach. Mass AI generation to trick rankings = violation of scaled content abuse

6. Impact of generative AI (AI Overviews + AI Mode) on SEO

TL;DR: Generative AI features such as AI Overviews / AI Mode are still based on Google's core Search ranking and quality systems. SEO is still SEO; there is no separate set of rules called "AEO/GEO".

Google uses 2 AI technologies for generative search:

Technology What it does
RAG (Retrieval-Augmented Generation) = grounding Uses core Search ranking to pull relevant pages, reviews specific information to generate answers, and displays clickable links
Query fan-out The model generates a set of related concurrent queries to supplement information. For example, "how to fix lawn full of weeds" will expand into "best herbicides for lawns" / "remove weeds without chemicals" / "how to prevent weeds"

5 SEO best practices that remain effective for generative AI

  1. Create unique, valuable, non-commodity content

    • Provide a unique POV (first-hand reviews vs summarizing others → the former has higher value)
    • Non-commodity: compare "7 Tips for First-Time Homebuyers" (commodity, anyone can write it) vs "Why We Waived the Inspection & Saved Money: A Look Inside the Sewer Line" (non-commodity, unique experience/expert perspective)
    • Good structure (paragraphs, headings), written for humans not for AI
    • Add high-quality images + video (see Complete Guide to Rich Features / Discover / Images / Video / Page Experience / Web Stories / SXG / Paywall)
    • Do not generate separate content for every possible query variant(violates scaled content abuse policies)
    • When using AI to assist generation, ensure compliance with Search Essentials + spam policies

  2. Maintain a clear technical architecture

  3. Optimize local / e-commerce details — complete Merchant Center / Business Profile information (see Complete Ecommerce SEO Guide (6 Surfaces / 4 Launch Strategies / Merchant Center / 6 SD Types / 3 Pagination Modes / 13 Review Guidelines))

Mythbusting: Things you do NOT need to do in the AI era

Myth Reality
llms.txt files / "AI-specific" markup Not needed. Google does not give special treatment to such files
"Chunking" (cutting content into small chunks for AI to understand) Not needed. Google can understand multi-topic pages
"Rewriting for AI" Not needed. AI understands synonyms; you do not need to stuff every long-tail variant
Pursuing "inauthentic mentions"(fake mentions) Useless. AI relies on both high-quality content and spam detection systems
Over-stacking structured data for AI Unnecessary. SD helps with rich results, but is not required for generative AI
AEO / GEO This is marketing jargon. From Google's perspective, it is just SEO

Agentic experience (forward-looking)

7. Complete list of Spam policies

Violating any of these → demotion / complete removal from search results / manual action.

Category Summary Key examples
Cloaking Cloaking Presenting different content to users and search engines Showing a travel page to search engines, but prescription drugs to users
Doorway abuse Doorway pages Creating intermediate pages targeted at specific queries to funnel users to the final destination Slight variants of multiple URLs / multiple domains pointing to the same page
Expired domain abuse Expired domain abuse Buying expired domains and hosting unrelated content to borrow their authority Hosting affiliate marketing on old government domains / selling commercial medicine on old charity medical domains
Hacked content Hacked content Malicious/spam content injected after a site is hacked code injection / page injection / content injection / hidden redirect
Hidden text & link Hidden text/links Content made only to trick search engines and hidden from human users White text on white background / text behind images / CSS off-screen placement / font-size 0 / opacity 0
Keyword stuffing Keyword stuffing Unnaturally stuffing keywords Phone number lists / lists of cities and regions / repeating the same phrase over and over
Link spam Link spam Link behavior primarily intended to manipulate rankings Buying or selling links / large-scale reciprocal linking / automated backlinks / exchanging links for goods/services / advertorials with optimized anchor text / optimized anchor text in forum signatures
Machine-generated traffic Automated traffic Automated queries to scrape Google results Rank-checking scraping tools
Malicious practices Malicious behavior malware / unwanted software / back-button hijacking Secretly installing software, changing the homepage / leaking privacy / blocking the back button
Misleading functionality Misleading functionality Pretending to offer a service that is not actually provided Fake app store credit generators / fake PDF merging tools that lead to ads
<a id="scaled-content-abuse"></a>Scaled content abuse Scaled content abuse Mass-producing low-value pages to trick rankings Mass AI-generated valueless pages / scraping feeds + synonym replacement / stitching together others' content / hiding the true scale across multiple sites
Scraping Scraped and reposted content Scraping content from other sites and posting it to trick rankings Reposting without adding value / copying + synonym replacement / media content compilation sites
Site reputation abuse Site reputation abuse Publishing third-party content on a host site to leverage its existing authority (content that would not rank on its own) Education sites publishing paid loan reviews / medical sites running "best casino" ads / news sites hosting white-label coupons
Sneaky redirects Sneaky redirects Sending search engines and users to different content Normal content on desktop / redirecting mobile users to spam domains
Thin affiliation Thin affiliate marketing Affiliate pages that copy merchant descriptions/reviews with no original content Template sites with cookie-cutter affiliate content
User-generated spam UGC spam User-generated spam content Forum spam / blog comment spam / spam uploads on file hosting sites
Legal removals Large volumes of valid copyright takedowns → entire site demoted Large volumes of DMCA complaints
Personal info removals Large volumes of personal information takedowns (involving exploitative practices) → demotion Doxxing / personal information exposure sites
Policy circumvention Continuing violations using subdomains / subdirectories / new sites → harsher penalties
Scam & fraud Impersonating official entities / fake contact information / scamming for money Impersonating customer support / fake merchant information

Exceptions: cases that do not count as site reputation abuse(to avoid false positives):

  • News agencies / press release services
  • Content syndication between media outlets
  • Forums / comment sections (UGC by design)
  • Columns / opinion pieces / editorial content
  • Advertorials / native advertising (intended to be shared directly with readers)
  • Affiliate links (with compliant link handling)
  • Third-party ad slots
  • Coupons pulled directly from merchants

8. Daily website maintenance checklist (condensed from the get-started guide)

When your website is already in Google's index and you want to keep optimizing it:

Control how Google crawls/indexes your site

Subtask How to do it See details in
Understand the full crawl/index/serve process Read §1 —
Duplicate content Set canonicals Complete Guide to Canonicals / Redirects / Site Migrations (including full HTTP status code table + 503 temporary outage playbook)
Make resources (images/CSS/JS) accessible Not blocked by robots.txt + accessible anonymously Complete Guide to Crawling and Indexing Control (robots.txt / noindex / X-Robots-Tag / data-nosnippet / rel)
robots.txt Block duplicate content / unimportant resources (icons/logos);do not use it for noindex Complete Guide to Crawling and Indexing Control (robots.txt / noindex / X-Robots-Tag / data-nosnippet / rel)
Sitemap Tell Google which pages are important + update frequency + non-text content (images/video) Complete Sitemap Guide (XML / RSS / Text + image / video / news / hreflang extensions + sitemap index)
Internationalization / multilingual hreflang Complete Guide to Internationalization (hreflang/multilingual/multi-region) + Explicit Content Tagging (SafeSearch/Adult)
Single URL migration 301 permanent / 302 temporary Complete Guide to Canonicals / Redirects / Site Migrations (including full HTTP status code table + 503 temporary outage playbook)
Full site migration 301 + sitemap + Search Console notification Complete Guide to Canonicals / Redirects / Site Migrations (including full HTTP status code table + 503 temporary outage playbook)
404 handling Return a real 404, do not serve soft 404s Complete Guide to Googlebot Crawling Mechanisms and Index Control (URL/Links/Mobile-first/Meta/Testing/AMP)

Links + crawl budget

Help Google understand your content

Content-specific guidelines

Page experience (user experience is a ranking factor)

Control search result presentation

See details in Full Overview of Search Result Visual Elements (Visual Gallery / Title / Snippet / Favicon / Sitelinks / Featured / AI / Translated / Preferred):

  • How to write title links / snippets
  • favicon
  • publication date
  • Limit snippet length or turn snippets off entirely

9. Several common SEO myths (compiled at the end of the seo-starter-guide)

Myth Truth
The meta keywords tag is useful Google does not use it
Keyword repetition is useful Not only is it useless, excessive repetition violates spam policies
Stuffing keywords in domain names / URL paths has almost no impact on rankings; it only affects breadcrumb display
TLDs (.com vs.org vs.asia) affect rankings They are only a weak signal for country-targeting, and have no effect otherwise
There is a magic number for content length There is no ideal length; write naturally, but varying your wording can help you match more searches
Which is better for SEO: subdomain vs subdirectory It is a business decision; Google does not prefer one over the other
Duplicate content will get you a penalty It will not (it is not a violation); it only wastes crawl resources
Heading order / count affects rankings It does not affect rankings (but it is friendly to screen readers)
E-E-A-T is a ranking factor It is not; it is a set of conceptual frameworks that help Google identify high-quality content

10. Promotion + do not overdo it

The most effective and lasting method is word of mouth — existing users telling their friends. It requires upfront investment in community participation to build up.

Other legitimate promotion methods:

  • Social media
  • Community participation
  • Online/offline advertising
  • Printing your URL on business cards / letterheads / posters
  • Sending newsletters to your audience (with consent)

Over-promotion backfires — it causes user fatigue and may be seen by search engines as manipulating search results.

11. Next steps + resources

Official learning path (English):

Neighboring pages on this wiki(full GSC docs tree):

Wiki Content
Complete Structured Data Overview (framework + quick lookup for 34 rich result types + choosing between JSON-LD/Microdata/RDFa) Full panorama of 33 structured data types (Product/Article/Recipe/Job/Movie, etc.)
Full Overview of Search Result Visual Elements (Visual Gallery / Title / Snippet / Favicon / Sitelinks / Featured / AI / Translated / Preferred) SERP elements such as snippets / sitelinks / title links / featured results / favicons
Complete Guide to Rich Features / Discover / Images / Video / Page Experience / Web Stories / SXG / Paywall Discover / Images / Web Stories / video / Page Experience / Core Web Vitals
Google ranking systems + Core/Spam Updates + business information setup core updates / spam updates / ranking systems guide
Complete Guide to Crawling and Indexing Control (robots.txt / noindex / X-Robots-Tag / data-nosnippet / rel) robots.txt / robots meta / block-indexing / prevent-images / nofollow
Complete Sitemap Guide (XML / RSS / Text + image / video / news / hreflang extensions + sitemap index) Full sitemap coverage (build/image/video/news/large sites)
Complete JavaScript SEO Guide (Basics + Diagnostics + Dynamic Rendering + Lazy Loading) JS SEO basics / dynamic rendering / lazy loading / fix-search-js
Complete Guide to Canonical Tags / Redirects / Site Migrations (Including full HTTP status code table + 503 temporary outage playbook) canonicalization / 301 / site move / URL structure
Complete Guide to Googlebot Crawling Mechanisms and Indexing Controls (URL/Links/Mobile-first/Meta/Testing/AMP) Googlebot / HTTP errors / AMP / mobile-first / file types
How to Use the Search Console + Analytics + Trends Trio (Traffic Diagnostics / Keyword Research / Looker Studio) Search Console + GA + Traffic Drop Diagnostics
Complete Guide to Security / Spam / Removals / Search Operators (malware + phishing + UGC + redacted + site:) security(malware/social engineering)+ search operators + prevent abuse
Complete Ecommerce SEO Guide (6 Surfaces / 4 Launch Strategies / Merchant Center / 6 SD Types / 3 Pagination Modes / 13 Review Guidelines) Complete Ecommerce SEO Series: 8 Articles
Complete Guide to Internationalization (hreflang/Multilingual/Multi-region) + Explicit Content (SafeSearch/Adult) Multilingual / Multiregional / Adult Content Guide

External World:

  • The local raw file (raw HTML) is at ~/kb/sources/reference/google-search-central/<原路径>.raw.html.gz(gitignored, kept locally)
  • Weekly incremental updates are triggered by gsc-crawler via launchd every Monday at 03:00; new/changed pages are automatically mirrored to ~/kb/inbox/gsc__*.md

2026-09 Addendum: How to Evaluate Claims Made by Third-Party SEO / GEO Tools

On 2026-06-05, official guidance placed third-party recommendations for traditional SEO, AEO (Answer Engine Optimization), and GEO (Generative Engine Optimization) under the same set of evidence review standards. The focus is not on the label, but on whether the recommendation states its basis and applicable conditions.

  1. First distinguish whether the other party is citing official rules or sharing their own experiential judgment. Experience can be valuable, but it should be clearly marked as a view based on data or practice, and not packaged as "Google says."
  2. Compare specific measures against official search and generative AI guidance before deciding whether to adopt them. Generating sitemaps, setting indexing directives, generating content, and predicting rankings are different tasks; do not use a single tool score to replace full judgment.
  3. Third-party tools cannot access Google's internal ranking data. The predictions they provide are their own estimates, not Google internal signals, and cannot guarantee ranking outcomes.
  4. Google does not evaluate third-party services; implications of being "Google approved/endorsed" cannot serve as a basis for procurement or implementation. Even if you use tools, you should view first-party actual data in Search Console.

Practical records should simultaneously document recommendations, source types, expected changes, and verification metrics. This way, even if an experiment is ineffective, you can distinguish between incorrect rules, implementation issues, and unmet tool predictions; you will not treat the use of the tool itself as optimization success.

Sources and Related Materials