Key Takeaways
- Six families: how search engines work, technical aspects, content and keywords, links, local SEO, visibility in AI.
- The top ten you should know first: crawl, indexing, SERP, keyword, search intent, title tag, backlink, Core Web Vitals, Google Business Profile, GEO.
- Usage: understand an audit or a quote, interpret Search Console data, and communicate with a service provider.
- Each term links, when available, to a fact sheet or a detailed guide.
The search engine optimization contains a lot of technical jargon, mixing English, acronyms, and the names of Google updates. This glossary compiles the sixty terms you’ll encounter most often, grouped by category and defined in one or two sentences. Terms that have a full entry on this site are linked.
How Engines Work
| Term | Definition |
|---|---|
| Crawl (exploration) | Search engine robots (Googlebot) navigating through pages via links. |
| Indexing | Indexing a page in the search engine's database; a page that is not indexed cannot be ranked. |
| Crawl Budget | The number of pages a search engine crawls on a website within a given period of time; a key consideration for large websites. |
| Algorithm | The complete set of ranking rules; updated continuously and through "core updates." |
| SERP | A search engine results page, featuring organic results, ads, a local pack, snippets, and AI Overviews. |
| Position / Ranking | A page's ranking in the SERP for a search query. |
| Position 0 / featured snippet | Snippet featured above the standard results. |
| AI Overview | A response generated by Google's AI at the top of certain SERPs, with cited sources. |
| PageRank | A historical algorithm that measures a page's authority based on its backlinks. |
| E-E-A-T | Experience, expertise, authority, reliability: quality criteria for Google evaluators. |
| YMYL | Sensitive topics (health, money, safety) that are subject to stricter quality standards. |
| Panda / Penguin | Updates in 2011 and 2012 to combat low-quality content and artificial links. |
Technical SEO
| Term | Definition |
|---|---|
| Title tag | Page title displayed in search results and on the tab. |
| Meta description | Summary displayed below the title in the results; click-through driver, no ranking. |
| Hn (H1, H2, H3) | Hierarchical content headings. |
| Meta robots | A tag that tells search engines whether to index a page or not, and whether to follow links or not. |
| Noindex | Instruction to not index a page. |
| Robots.txt | A file in the root directory that allows or denies access to parts of the site. |
| XML Sitemap | List of URLs from the site provided to search engines. |
| Canonical | A tag that identifies the reference URL among duplicate entries. |
| Duplicate content | The same content is accessible at multiple addresses. |
| HTTP Codes | 200, 301, 404, 500: Page status codes for browsers and search engines. |
| 301 Redirect | A permanent redirect from one URL to another, with a transfer of authority. |
| Core Web Vitals | Three experimental measures: LCP (loading), INP (responsiveness), CLS (visual stability). |
| Responsive design | Optimizing a page for all screen sizes; Google indexes the mobile version. |
| Structured Data (Schema.org) | Markup that describes the content to search engines (article, product, FAQ, company). |
| Enriched Results | Special displays (stars, FAQs, prices) generated using structured data. |
| URL rewriting | Rewrite addresses to human-readable URLs. |
| HTTPS | Secure login has been required since 2014. |
| Log (log analysis) | Check the server logs to see what Googlebot is actually crawling. |
Content and Keywords
| Term | Definition |
|---|---|
| Keyword / search term | A search term entered by a user that a page is optimized for. |
| Research Objective | What internet users want: to get information, browse, compare, and buy. |
| Longline | Specific, low-volume search terms—plentiful and easy to rank for. |
| Research Volume | Monthly number of searches for a query. |
| Difficulty | Estimating competition for a search query. |
| Cannibalization | Several pages from a website competing for the same search query. |
| Semantic cocoon | Pages organized by topic in a hierarchical structure. |
| Internal linking | Links between pages on the same website. |
| Anchor | Clickable text in a link. |
| Thin content | Page with no unique content; short or generic. |
| Content Marketing | A strategy for creating useful content to attract and persuade. |
| CTR (click-through rate) | Clicks/impressions in search results; visible in Search Console. |
Links and Popularity
| Term | Definition |
|---|---|
| Backlink | A link from an external website to yours. |
| Netlinking | Backlink Acquisition Strategy. |
| Reference Domain | A separate website that links to you; the most telling indicator. |
| Dofollow / nofollow / sponsored | Attributes that indicate whether a link passes authority. |
| Domain Authority | Proprietary scores (Trust Flow, Domain Rating) that estimate a website's strength. |
| Disavowal | A file that instructs Google to ignore certain links; for exceptional use only. |
| Black hat | Prohibited manipulation techniques. |
Local SEO
| Term | Definition |
|---|---|
| Google Business Profile | Free business listing (formerly Google My Business). |
| Local Pack | A block of three schools with a map at the top of the results. |
| NAP | Name, address, phone number: consistency is essential on the web. |
| Local quote | Listing of your business in a third-party directory or on a third-party website. |
| Reviews | Customer ratings and reviews; local ranking criteria. |
| Service Area | Geographic scope of your customers. |
Insight into AI
| Term | Definition |
|---|---|
| GEO | Generative Engine Optimization: Being Cited by ChatGPT, Perplexity, Gemini, and AI Overviews. |
| LLM | Large language model, the backbone of AI assistants. |
| RAG | Real-time AI-powered search before drafting a response. |
| Citation / Reference | A link or brand name included in an AI response. |
| Entity | An identifiable entity (company, person, product) that search engines link together. |
| llms.txt | A file designed to guide AI bots to a website's essential content. |
The fields of advertising and analytics have their own specific terminology: Google Ads Glossary and Google Analytics Glossary. To get down to business, our Comprehensive SEO audit applies most of these concepts.
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Frequently Asked Questions
What is the difference between crawling and indexing?
Crawling is the process of exploring: the bot reads the page. Indexing is the process of adding a page to the search engine’s database. A page can be crawled without being indexed (Google deems it to have no value, or it has a “noindex” tag); this is the “crawled, currently not indexed” status in Search Console.
What does E-E-A-T stand for?
Experience, Expertise, Authoritativeness, Trustworthiness: experience, expertise, authority, and reliability. These are the criteria that Google’s quality raters use to evaluate content, particularly on sensitive topics. They include an identified author, sources, evidence of experience, and a verifiable reputation.
What is the long tail in SEO?
All of the specific, low-volume search queries (such as “SEO audit for e-commerce sites in Nantes”) that, when combined, account for the majority of traffic. They are easier to rank for and convert better than highly competitive generic search terms.
Which SEO terms have changed with the advent of AI?
The vocabulary has expanded to include: GEO (generative engine optimization), AI Overview (AI response at the top of Google search results), citation and mention (appearance in an AI response), entity, RAG, and llms.txt. The fundamentals (crawling, indexing, content, links) remain the foundation upon which these new terms are built.