What you will find in this glossary
We have gathered the terms that come up across any real SEO project: from fundamentals like CTR or backlink to more recent concepts such as GEO, AEO or E-E-A-T. Every definition is deliberately short (1-3 sentences) so it works as a quick reference and, at the same time, can be cited by AI engines like ChatGPT, Perplexity or Google AI Overviews. If you miss a term, drop us a line and we will add it.
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- 301 RedirectTechnical SEO
- Permanent HTTP redirect. The correct way to signal that a URL has changed: passes most of the authority to the new URL.
- 302 RedirectTechnical SEO
- Temporary HTTP redirect. Using 302 for permanent changes is a common mistake that dilutes authority transfer.
- 404 Status CodeTechnical SEO
- HTTP response indicating the requested URL does not exist. A reasonable amount of 404s is normal; many often signal architecture or migration issues.
A
- AEO(Answer Engine Optimization)AI, GEO & AEO
- Optimisation for answer engines. Works FAQs, FAQPage/HowTo structured data and direct formats that can be reused as answers.
- AI Overviews(SGE, Search Generative Experience)AI, GEO & AEO
- AI-generated summaries Google displays above organic results. Industry estimates put their presence at a significant and growing share of searches, especially on informational queries.
- Alt textOn-page SEO
- Alternative text of an image, read by screen readers and search engines. Helps images rank and improves accessibility.
- Anchor textOn-page SEO
- Visible text of a link. Provides context about the destination page and is an important relevance factor, both for internal and external links.
B
- Backlink(inbound link)Off-page SEO
- Link from another site to ours. One of the historically most important ranking factors; quality weighs far more than quantity.
- Black hat SEOFundamentals
- Techniques that manipulate search algorithms and violate Google's guidelines (cloaking, paid link networks, hidden content). Penalised and off-limits in serious projects.
- Bounce rateAnalytics
- Percentage of single-page sessions without interaction. In GA4 it's the inverse of engagement rate and should be interpreted carefully.
C
- Canonical(rel=canonical)Technical SEO
- HTML tag telling Google which URL is preferred when there is duplicate or very similar content between pages. Prevents cannibalisation issues.
- CLS(Cumulative Layout Shift)Technical SEO
- Measures visual stability — how much elements move during load. Good value: under 0.1. Images without explicit dimensions are the most common cause.
- Consent ModeAnalytics
- Google feature that adapts tag behaviour based on the user's cookie consent. Required in the EU after GDPR and the Digital Markets Act.
- Conversion rateAnalytics
- Percentage of visitors who complete a target action (purchase, lead, subscription). The KPI that best connects SEO traffic with business outcome.
- Conversion trackingAnalytics
- Configuration of GA4, Google Ads and other platforms to record when a visitor completes a business action (purchase, lead, signup). The basis of any attribution.
- Core Update(core algorithm update)Fundamentals
- Major Google algorithm update, several times a year, that re-evaluates overall site quality. Usually shakes rankings for 2-3 weeks and is the hardest E-E-A-T test.
- Core Web Vitals(CWV)Technical SEO
- Three official Google metrics that measure user experience on a page: LCP, INP and CLS. Part of the ranking factors since 2021.
- CPA(Cost Per Acquisition)Fundamentals
- Cost of generating a conversion (lead or sale). It is the metric that best connects marketing investment with real profitability.
- CPC(Cost Per Click)Fundamentals
- Amount the advertiser pays for each click on an ad. It depends on competition and on ad quality (Quality Score).
- Crawl BudgetTechnical SEO
- Amount of URLs Googlebot is willing to crawl on a site in a given period. Critical on sites with hundreds of thousands of pages.
- CrawlingTechnical SEO
- Process by which search engines discover URLs by following links and reading sitemaps. First step before indexing.
- CrUX(Chrome User Experience Report)Technical SEO
- Public Google database with real Core Web Vitals data collected through Chrome. The source of "field data" in PageSpeed Insights and Search Console.
- CTR(Click Through Rate)Fundamentals
- Percentage of users who click a result over total impressions. A compelling meta title is the main lever to improve it.
D
- Digital PROff-page SEO
- Digital public-relations strategy that pursues mentions and links in recognised media. Today's most sustainable form of link building.
- DisavowOff-page SEO
- Google Search Console tool used to tell Google to ignore certain toxic backlinks when evaluating the site.
- DofollowOff-page SEO
- Link that passes authority to the linked site (default state, no special rel attribute). The links with the most SEO value.
- Domain authority(DA, Domain Rating, DR)Off-page SEO
- Tool-specific metric (Moz DA, Ahrefs DR) that estimates the strength of a domain. Not an official Google factor but correlates with rankings.
- Duplicate contentOn-page SEO
- Identical or very similar content blocks reachable through multiple URLs. Dilutes authority and creates cannibalisation; solved with canonicals and redirects.
E
- E-E-A-T(Experience, Expertise, Authoritativeness, Trustworthiness)On-page SEO
- Google framework that values Experience, Expertise, Authoritativeness and Trustworthiness. Critical in YMYL sectors (health, finance, legal) and increasingly in GEO/AEO.
- Practical application: Clinics and healthcare · Finance and insurance · Lawyers and law firms · Online education and training
F
- Featured snippet(position 0)SERPs & results
- Highlighted box that answers a query directly at the top of the results. Captures a significant share of the CTR.
G
- GA4(Google Analytics 4)Analytics
- Current version of Google Analytics, event-based. Replaced Universal Analytics in July 2023.
- GBP(Google Business Profile, Google My Business)Local SEO
- Free Google listing for businesses with an address or service area. The central piece of local SEO, appearing in Local Pack and Maps.
- Practical application: Restaurants and hospitality · Clinics and healthcare · Lawyers and law firms · Real estate
- Generative AIAI, GEO & AEO
- Models able to generate text, images or video from a prompt. In search this includes ChatGPT, Perplexity, Claude, Gemini and Google's AI Overviews.
- GEO(Generative Engine Optimization)AI, GEO & AEO
- Optimisation for generative engines. Aims to have content cited by ChatGPT, Perplexity and similar engines through clear definitions, verifiable data and semantic structure.
- Google DiscoverSERPs & results
- Personalised Google feed on mobile that shows content to the user without an explicit search. Rewards fresh editorial content with authorship and Article structured data.
- Google penalty(manual action)Off-page SEO
- Manual or algorithmic action that reduces a site's visibility. Manual actions are notified in Search Console; algorithmic ones are detected through traffic drops.
- Google-ExtendedAI, GEO & AEO
- User agent Google uses to control whether site content can be used to train its AI models (Gemini, Bard). Managed via robots.txt.
- GPTBotAI, GEO & AEO
- OpenAI crawler that collects content to train and power ChatGPT answers. Allowed or blocked via robots.txt.
- Gray hat SEOFundamentals
- Grey area between white and black hat. Practices not explicitly forbidden but risky. Not recommended where the cost of a penalty is high.
- GSC(Google Search Console)Analytics
- Free Google tool showing how a site looks from Google: impressions, clicks, average position, crawl errors, indexing issues.
- GTM(Google Tag Manager)Analytics
- Tag manager that lets you add and edit scripts (analytics, ads, events) without touching the site's code. The standard for implementing GA4.
H
- H1On-page SEO
- Main heading of a page. There must be exactly one per page and it should reflect the main topic with the target keyword.
- HallucinationAI, GEO & AEO
- Made-up answer presented as true by an LLM. A solid GEO/AEO strategy reduces the chance that AI invents information about your brand.
- Heading hierarchy(H2, H3)On-page SEO
- H1 > H2 > H3 structure that organises content. Improves accessibility, human readability and LLMs' ability to extract citable sections.
- HeatmapAnalytics
- Visualisation of where users click, hover and scroll on a page. Tools like Hotjar or Microsoft Clarity help optimise conversion and UX, not ranking.
- Helpful Content Update(HCU)Fundamentals
- Google update prioritising content written by people for people and penalising mass-produced or low-value content. Now integrated into the core system.
- hreflangTechnical SEO
- Attribute that signals the language and region of a page. Essential on multilingual sites to avoid duplicate content across versions.
I
- Image searchSERPs & results
- Google's visual search where the user provides an image or finds it among results. Optimising filenames, alt text and ImageObject schema improves visibility.
- ImpressionAnalytics
- Every time a page or ad is shown to the user in results. In GSC it represents how many times the site appeared in the SERPs.
- IndexingTechnical SEO
- Process by which search engines store and organise crawled pages so they can be served in search results.
- INP(Interaction to Next Paint)Technical SEO
- Core Web Vitals metric measuring the latency of user interactions with the page. Replaced FID in 2024. Good value: under 200 ms.
- Internal linkingOn-page SEO
- Network of links between pages of the same domain. Distributes authority, helps crawling and thematically reinforces content pillars.
- International SEOTechnical SEO
- Set of techniques to rank a site across multiple countries or languages. Covers ccTLD/subdirectory architecture, hreflang, localised content and per-market strategy.
J
- JavaScript SEOTechnical SEO
- Discipline that ensures JS-built sites (React, Vue, Angular) are crawlable and indexable. Covers SSR, prerender, hydration and DOM handling.
- JSON-LDTechnical SEO
- Google's recommended format for implementing Schema.org structured data. Inserted as a <script type="application/ld+json"> block in the HTML.
K
- KeywordKeywords & intent
- Term or phrase a user types into a search engine. Defines the intent we want to cover with each page.
- Keyword cannibalisationOn-page SEO
- Situation in which two or more pages of the same site compete for the same search intent. Solved by consolidating content or applying canonicals.
- Keyword Difficulty(KD)Keywords & intent
- Metric that estimates how hard it is to rank for a keyword. Combines authority of ranking domains and other tool-specific factors.
- Keyword stuffingOn-page SEO
- Practice of saturating content with keywords. Obsolete and penalisable: it harms more than it helps, and has done so for years.
- Knowledge PanelSERPs & results
- Side panel with information about entities (companies, people, places) in SERPs. Generated from the Knowledge Graph and official sources.
- KPI(Key Performance Indicator)Fundamentals
- Key Performance Indicator. In SEO the useful KPIs are qualified organic traffic, conversions and attributable revenue, not just rankings.
L
- LCP(Largest Contentful Paint)Technical SEO
- Time taken to render the largest visible element on the page (usually an image or text block). Good value: under 2.5 seconds.
- LighthouseTechnical SEO
- Automated Google audit integrated into Chrome DevTools and PageSpeed Insights. Reports performance, accessibility, basic SEO and best practices with metrics and recommendations.
- Link buildingOff-page SEO
- Strategy to acquire quality backlinks for a site. Today it must be based on editorial relevance and real authority, not mass buying.
- LLM(Large Language Model)AI, GEO & AEO
- Large-scale language model trained on massive text data. The basis of ChatGPT, Claude, Gemini and most generative AI engines.
- LLMO(LLM Optimization)AI, GEO & AEO
- Technical optimisation for language models: HTML semantics, verifiable authorship with sameAs, external citations and AI-bot handling in robots.txt.
- Local citationLocal SEO
- Mention of a business on another website that includes its NAP. It does not need a link to send geographic relevance signals to Google.
- Practical application: Restaurants and hospitality · Lawyers and law firms · Clinics and healthcare
- Local Pack(Map Pack)SERPs & results
- Block with three local businesses and a map shown on geographically intended searches. The main objective of local SEO.
- Log analysisTechnical SEO
- Analysis of server log files to understand how Googlebot and other bots crawl the site. Essential in advanced and enterprise technical SEO.
- Long tailKeywords & intent
- Long, specific keywords with low individual volume but high conversion rates and low competition. Together they add up to most real SEO traffic.
M
- Meta descriptionOn-page SEO
- Summary of a page's content shown under the title in SERPs. Not a ranking factor but strongly influences CTR.
- Meta title(title tag)On-page SEO
- HTML title that appears on the browser tab and as the linked headline in Google results. The on-page factor with the biggest impact on CTR.
- Mobile-First IndexingTechnical SEO
- Google's policy of using the mobile version of a site as the reference for indexing and ranking. Active by default on virtually every site.
N
- NAP(Name, Address, Phone)Local SEO
- Business Name, Address and Phone. NAP consistency across local directories is a key trust signal for local SEO.
- Practical application: Restaurants and hospitality · Clinics and healthcare · Lawyers and law firms
- nofollowTechnical SEO
- rel attribute telling the search engine not to pass authority through a link. Google now treats it as a hint rather than a strict directive.
- noindexTechnical SEO
- Meta robots directive telling search engines not to include that page in their results. Useful for low-value pages or internal search results.
P
- Page authority(PA, URL Rating)Off-page SEO
- Metric that estimates the strength of a specific URL. Useful for comparing pages within the same domain or between direct competitors.
- PageSpeed Insights(PSI)Technical SEO
- Free Google tool that evaluates page performance combining field data (CrUX) and lab data (Lighthouse). Standard for auditing Core Web Vitals.
- PaginationE-commerce SEO
- Splitting long listings (categories, blog) across several pages. Well-configured pagination lets Google discover every product without duplicate content.
- People Also Ask(PAA)SERPs & results
- Expandable block of related questions Google displays. A goldmine for keyword research and structuring FAQs.
- Pillar pageKeywords & intent
- Long, comprehensive page covering a central topic. The centre of a topic cluster and usually the page that ranks for the main keyword.
- Post-update recovery(core update recovery)Fundamentals
- Specialised service to diagnose which pages and patterns lost visibility after a core update and design the recovery plan. Combines SEO and editorial analysis.
- PPC(Pay Per Click)Fundamentals
- Advertising model where you pay each time a user clicks on an ad. The dominant model on Google Ads and Microsoft Ads.
- Product descriptionsE-commerce SEO
- Descriptive text for each product. They should be unique, persuasive and solve real buyer doubts, avoiding manufacturer-default copy.
- Product rich snippetE-commerce SEO
- Rich result for product pages generated with Product structured data. Shows price, rating, availability and increases CTR.
- Programmatic SEOTechnical SEO
- Mass, automated creation of landings from templates + structured data (e.g. "X in Y"). Works when there is real per-combination value; done badly it generates thin content.
R
- ReviewsLocal SEO
- Customer reviews on GBP and other platforms. Their number, frequency and rating are direct ranking factors in local SEO.
- Rich SnippetsTechnical SEO
- Search results with extra visual elements (stars, price, FAQs, breadcrumbs…) generated from structured data.
- ROAS(Return On Ad Spend)Fundamentals
- Revenue generated per euro invested in advertising. It's the ROI specific to ad spend.
- robots.txtTechnical SEO
- Text file at the root of a domain telling crawlers which parts of the site they may or may not crawl. Not a security mechanism: a voluntary directive.
- ROI(Return on Investment)Fundamentals
- Profit obtained in relation to the investment made. In SEO it is measured over the medium-long term because effects are not immediate.
S
- Schema CourseTechnical SEO
- Structured data for courses and training programmes. Lets Google show dates, mode, duration and language in education-related results.
- Schema HowToTechnical SEO
- Structured data describing a step-by-step process. Generates rich snippets with steps and is especially well cited by LLMs when a user asks "how to X".
- Schema LocalBusinessLocal SEO
- Structured data for physical businesses with an address. Includes hours, service area, ratings and categories. Essential to reinforce local SEO and the GBP listing.
- Schema OrganizationTechnical SEO
- Structured-data type describing the company that owns the site. Lets Google and LLMs identify it as an entity with logo, address, contact and sameAs.
- Schema ProductE-commerce SEO
- Product page structured data. Includes price, availability, rating, brand and SKU. Activates product rich snippets in Google and Google Shopping.
- Schema.org(structured data)Technical SEO
- Standard structured-data vocabulary used to describe content to search engines. Powers rich snippets and improves comprehension by LLMs.
- Search intentKeywords & intent
- What the user wants to achieve with a search. Classified as informational, navigational, commercial or transactional.
- Search volumeKeywords & intent
- Estimated monthly searches for a keyword. It's approximate data: different tools give different numbers for the same keyword.
- SEM(Search Engine Marketing)Fundamentals
- Marketing on search engines through paid ads, primarily Google Ads. Often confused with SEO; they are actually complementary channels.
- SEO(Search Engine Optimization, web positioning)Fundamentals
- A set of practices that improve a site's visibility in the organic results of search engines. It covers three fronts: technical, content and authority.
- SEO agencyFundamentals
- Company providing professional search-positioning services to other companies. Typically combines consultants, technical specialists and writers in one team.
- SEO consultantFundamentals
- Senior professional who defines the SEO strategy of a project and oversees execution. Usually the client's direct contact and brings business judgement.
- SEO migrationTechnical SEO
- Process of changing a site's domain, URL structure, CMS or design without losing organic traffic. Requires a 301 redirect map, crawl validation and post-migration monitoring.
- SERP(Search Engine Results Page)SERPs & results
- Search-engine results page. Includes organic results, ads, featured snippets, AI Overviews, videos, images and other blocks.
- Server-side taggingAnalytics
- Google Tag Manager model where events are first sent to your own server before Analytics. Reduces browser load and improves privacy and reliability.
- SitelinksSERPs & results
- Additional links to internal pages Google shows under a result. Appear automatically on brands with good architecture and authority.
- Sitelinks SearchboxSERPs & results
- Internal search box Google shows below the main result for brands with strong SEO. Activated with WebSite + SearchAction structured data.
- sitemap.xmlTechnical SEO
- XML file listing important URLs to help search engines crawl the site. Especially useful for large or complex sites.
- Soft 404Technical SEO
- Page that responds with status 200 but whose content is an error page. Google treats it as a 404 but less efficiently.
T
- Thin contentOn-page SEO
- Pages with scarce, low-value or auto-generated content. Google considers them low quality and they can drag the rest of the site down.
- Topic clusterKeywords & intent
- Content structure formed by a pillar page and several satellite articles covering subtopics. Reinforces the site's topical authority.
- Toxic backlinkOff-page SEO
- Backlink that may harm rankings — coming from a spammy, penalised or manipulative site. Mitigated through analysis and the disavow tool.
U
- UTM parameters(UTMs)Analytics
- Parameters added to a URL (utm_source, utm_medium, utm_campaign) to identify the traffic source in Google Analytics. Essential for external campaigns.
V
- Voice searchSERPs & results
- Searches performed by voice with assistants (Siri, Google Assistant, Alexa). They reward direct answers, natural language and featured snippet placement.
W
- White hat SEOFundamentals
- SEO practices that strictly follow Google's guidelines. Sustainable long-term and the only sensible approach for professional projects.
Y
- YMYL(Your Money Your Life)On-page SEO
- Google category for pages that affect health, finances, safety or wellbeing. They receive stricter quality and E-E-A-T criteria than other content.
- Practical application: Clinics and healthcare · Finance and insurance · Lawyers and law firms
Z
- Zero-click searchSERPs & results
- Searches that end without the user clicking any result. According to SparkToro, they exceeded 58% of Google searches globally in 2024; the share keeps growing as AI Overviews spread.