Glossary from A to Z

5xx server errors are HTTP status codes from 500 to 599.

10x content is an SEO industry concept for content that should be ten times better than the best result already ranking for a topic.

The status code 200 OK means that an HTTP request has succeeded.

A 301 redirect is a server response with the HTTP status code 301 Moved Permanently.

A 302 redirect (status code 302 Found) tells browsers and crawlers that a resource is temporarily available at a different URL, given in …

304 Not Modified is an HTTP status code that tells a client its cached copy of a resource is still current, so the server does not send …

A 307 redirect (Temporary Redirect) is an HTTP status code that sends a client to another URL for a limited time.

A 308 redirect (Permanent Redirect) is an HTTP status code for a permanent move.

The HTTP status code 401 Unauthorized means a request lacks valid authentication credentials for the requested resource.

403 Forbidden is an HTTP status code in the 4xx class.

A 404 error (404 Not Found) is the HTTP status code a server returns when it finds nothing at the requested URL.

410 Gone is an HTTP status code that says a resource is no longer available on the server and that this is likely to be permanent.

The HTTP status code 429 Too Many Requests means a client has sent too many requests in a given time.

451 Unavailable For Legal Reasons is an HTTP status code that signals the server denies access to a resource because of a legal demand.

A 500 Internal Server Error is a generic HTTP server error.

The HTTP status code 502 Bad Gateway means a server acting as a gateway or proxy received an invalid response from an upstream server …

The HTTP status code 503 Service Unavailable means the server is not ready to handle the request.

The HTTP status code 504 Gateway Timeout means a server acting as a gateway or proxy did not receive a timely response from the upstream …

Above the fold is the part of a web page that is visible in the browser window when the page loads, before anyone scrolls.

The accessibility tree is a representation of a page that the browser derives from the DOM and exposes to assistive technologies such as …

An access log is the file in which a web server records each request it handles, one line per request.

ads.txt (Authorized Digital Sellers) is a public text file that lets publishers declare which companies may sell their digital ad inventory.

AEO (answer engine optimization) describes measures that aim to make content appear as an answer in AI-based systems such as ChatGPT …

Affiliate SEO is search engine optimization for websites that earn commissions through affiliate links, meaning payment for referred …

The Agent2Agent protocol (A2A) is an open protocol that lets AI agents built on different frameworks and by different vendors communicate …

Agent analytics, in an SEO context, is the analysis of visits by AI bots and AI agents to a website, usually based on server or CDN logs.

An Agent Card is a JSON document in which an AI agent describes itself under the Agent2Agent (A2A) protocol: its name, what it can do …

An agentic browser is a web browser with a built-in AI agent that plans and carries out tasks on a user's behalf, such as opening pages …

Agentic commerce describes purchases in which an AI agent acts on a person's behalf to find, compare, and buy products, up to and …

The Agentic Commerce Protocol (ACP) is an open standard for connecting buyers, their AI agents and businesses so that purchases can be …

Agentic search is a search approach in which an AI agent decides when to search, writes the queries, reads the results and, if needed …

The Agent Payments Protocol (AP2) is an open protocol from Google for payments that AI agents make on behalf of users.

Agent readiness describes how well AI agents can discover, read and use a website.

An AI agent is a system in which a language model decides on its own which steps and tools to use to reach a goal.

An AI brand mention occurs when an AI system such as ChatGPT, Gemini or Perplexity names a brand in the text of its answer.

An AI chatbot is software that holds conversations with people and answers their input automatically.

An AI citation is a source reference in an answer from an AI system, usually a link or footnote to the web page a statement came from.

AI content detection means methods and tools that try to estimate whether a text, image or video was generated by an AI.

An AI crawler is an automated program that fetches web pages for AI applications.

AI-generated content is text, images, audio or video created fully or partly with generative AI.

An AI hallucination is an output from a language model that sounds plausible but is false, irrelevant or invented.

AI Mode is a search experience in Google Search that answers questions with an AI-generated response in a conversational view, alongside …

AI opt-out here means the ways a website can limit how Google's generative search features use its content, which are AI Overviews and AI …

AI Overviews are AI-generated summaries that Google Search shows above the regular results for some queries.

An AI product feed is a file that provides a shop's product data in a defined format so that AI assistants can find, compare and display …

AI referral traffic is made of visits that arrive through a link in an answer from an AI assistant such as ChatGPT, Gemini or Perplexity.

AI search refers to search systems that answer a query with text generated by a language model and link to the web sources the answer …

An AI search crawler is a crawler that fetches web pages for the search feature of an AI product, so the product can surface and link them …

AI sentiment in the SEO and GEO sense is the tone with which an AI system describes a brand, product or person in its answers, for example …

AI SEO is a loose term with two common meanings.

AI share of voice, often called share of model, measures how often a brand appears in answers from AI assistants such as ChatGPT, Gemini …

AI snippet is an informal SEO label for the text that Google shows from a page inside its AI answers, or for the AI-written summary itself.

ai.txt is a proposed file name for a text file in which website operators state how AI systems may use their content.

AI visibility describes how often and in what way a brand, product or website appears in answers from AI systems such as ChatGPT …

AI visibility tracking measures how often and in which context a brand or domain appears in answers from AI systems, either as a name in …

AJAX (Asynchronous JavaScript and XML) is a technique where a web page requests data from the server in the background and updates only …

An alert is an automatic notification that fires when a monitored value meets a condition set in advance.

An alert threshold is a limit set for a measured value.

An algorithmic penalty is an informal SEO term for a drop in rankings caused by Google's automated systems rather than by a human reviewer.

Algorithm update trackers, also called SERP volatility tools, measure how strongly Google's search results change over time.

Alt text (alternative text) is a short written description of an image, placed in the alt attribute of an HTML img element.

Amazonbot is Amazon's web crawler.

AMP (Accelerated Mobile Pages) is an open-source framework for fast-loading web pages, announced by Google in 2015.

Amzn-SearchBot is an Amazon crawler that, according to Amazon, improves search experiences in Amazon products and services.

Amzn-User is an Amazon fetcher that loads web pages on behalf of users.

The anchor element <a>, often called anchor tag, creates a hyperlink in HTML.

Anchor text (link text) is the visible, clickable text of a link.

In SEO, an annotation is a short dated note placed on a chart of performance data.

Anomaly detection is the identification of observations, events or data points that deviate from what is usual or expected.

Anonymized queries are search queries that Google leaves out of Search Console to protect user privacy.

An answer engine is a search system that responds to a question with a written answer and source links, instead of putting a list of …

anthropic-ai is a user agent name that appears in many robots.txt files to keep Anthropic's crawlers out.

An API (application programming interface) is, in MDN's wording, a set of features and rules in a software program that lets other …

Applebot is Apple's web crawler.

ARIA (Accessible Rich Internet Applications, specifically WAI-ARIA) is a W3C specification for giving HTML elements extra information for …

An article directory is, in SEO, a website where users submit articles and place a link to their own site in the text or author box.

Article schema is structured data that describes an article page: its headline, images, dates and author.

Article spinning is the automatic rewriting of an existing text.

Artificial intelligence (AI) is a broad term for computer systems that handle tasks which normally call for human intelligence, such as …

Marketing attribution assigns credit for a conversion to the channels and touchpoints that led to it.

An author byline is the line that names who wrote a piece of content.

Automatically generated content is content that software produces, for example from templates and data feeds, through translation, or with …

Availability is the share of time in which a website or service responds correctly.

Average position is a metric in the Google Search Console performance report.

The back/forward cache (bfcache) is a browser optimization that keeps a complete snapshot of a page in memory when a user navigates away.

A backlink (also inbound link) is a link from another website to a page on your site.

Bad bots (also called rogue bots) are automated programs that access a website against the operator's wishes or ignore its rules.

Bad neighborhood is an SEO term for a group of spam sites that a website is connected to through links.

A baseline crawl, also called a benchmark crawl, is a full crawl of the current website taken before a major change such as a relaunch or …

BERT (Bidirectional Encoder Representations from Transformers) is an AI system Google uses to understand how combinations of words express …

The BFSG (Barrierefreiheitsstärkungsgesetz, German Accessibility Act) of July 16, 2021 sets accessibility requirements for certain …

Bingbot is the web crawler of Microsoft Bing.

Bing Webmaster Tools is Microsoft's platform for site owners to monitor how their website performs in Bing.

Black hat SEO means optimization techniques that violate the guidelines of a search engine in order to improve rankings through deception.

Blocked resources are CSS, JavaScript, image, and other files that a crawler is not allowed to fetch while rendering a page, usually …

Blocking AI bots means denying specific AI crawlers and fetchers access to a website.

Boilerplate is standard text that is reused with little change in many documents.

Bot management means detecting automated requests to a website, classifying them and deciding what happens next.

Bot traffic is any traffic to a website that comes from automated programs instead of people.

Bot verification is the check whether a crawler really belongs to the operator named in its user agent.

Bounce rate is the share of visits to a website that end without engagement.

A branded keyword is a search term that contains a brand name, a variant or misspelling of it, or a product of the brand.

Brand mentions are places on the web that name a brand or domain.

A brand SERP is the search results page that appears when someone searches for a brand or company name.

Brand signals in branding means the elements that make a brand recognizable, such as name, logo and colors.

Breadcrumb navigation (breadcrumbs) is a row of links, usually above the main content, that shows the path from a website's home page to …

Breadcrumb schema is BreadcrumbList structured data that describes where a page sits in the site hierarchy.

A broken link is a hyperlink whose target cannot be loaded, usually because the target page returns an error such as 404 or does not …

Broken link building is a link building method.

A browser agent is an AI system that operates a web browser the way a person does.

Browser caching (also called HTTP caching) means that a browser stores a copy of a response, such as an image, stylesheet or script, and …

A business directory is a website or printed listing that sorts businesses into categories.

Buying links means giving money, goods or services in return for a link to your site.

Bytespider is a web crawler attributed to ByteDance, the company behind TikTok.

Cache-Control is an HTTP header that tells browsers and shared caches such as CDNs whether and for how long they may store a response.

A call to action (CTA) is an element that asks visitors to take a specific next step.

Canonicalization in SEO is the process of choosing one preferred URL when the same or very similar content is reachable under several URLs.

A canonical tag is a <link rel="canonical"> element in the <head> of a page that names the preferred URL when the same or very similar …

A carousel rich result is a Google Search feature in which several entries from one site appear as cards that users can swipe through.

A category page in e-commerce is a page that groups related products under one URL and leads visitors to the product detail pages.

CCBot is the web crawler of Common Crawl, a non-profit that maintains an open repository of web crawl data.

A ccTLD (country code top-level domain) is a top-level domain with two letters that is assigned to a country or territory, such as .de for …

A CDN (content delivery network) is a geographically distributed network of servers that stores copies of a website's files and delivers …

Change monitoring (also called website change detection) is the automated comparison of a web page or file against its earlier version …

The Change of Address tool is a feature in Google Search Console for telling Google that a website has moved to a different domain, for …

ChatGPT agent is the OpenAI feature that lets ChatGPT carry out multi-step tasks on the web for a user.

ChatGPT-User is an OpenAI user agent that fetches web pages when someone using ChatGPT or a Custom GPT triggers an action.

The Chrome UX Report (CrUX) is a public Google dataset that reflects how real Chrome users experience websites.

Chunking, in the context of AI search, means splitting long documents into smaller passages, called chunks, that a system stores, searches …

Circle to Search is a Google feature for Android phones that searches for anything on the screen without leaving the current app.

Citability in generative engine optimization (GEO) describes how likely it is that a passage of content is selected and cited by an AI …

ClaudeBot is the web crawler of Anthropic, the company behind the AI assistant Claude.

Claude-SearchBot is an Anthropic crawler that navigates the web to improve the quality of search results for Claude users.

Claude-User is the user agent Claude, Anthropic's AI assistant, uses to access websites when a person asks Claude a question.

A click path (also clickstream) is the sequence of pages a visitor views on a website, in the order they were viewed.

Clicks in SEO count how often users clicked a link to your website in Google Search results.

Clickstream data is the recorded sequence of pages a user visits and the clicks the user makes along the way.

Click-through rate (CTR) is the share of people who click a link, ad, or search result after seeing it.

Client-side rendering (CSR) is a technique in which JavaScript builds the HTML of a page in the browser.

Cloaking in SEO means serving search engine crawlers different content than human visitors under the same URL.

A CMS (content management system) is software for creating, editing, managing and publishing digital content, usually website content …

A CMS migration is the move of a website to a different content management system, for example from WordPress to a headless CMS.

Co-citation means that two documents, pages or brands are cited together by a third source, without citing each other.

cohere-ai is a user agent token attributed to the AI company Cohere.

The Combined Log Format is a line format for web server access logs.

Comment spam is unwanted posts under articles or in forums, usually generated automatically and carrying links to other sites.

Commercial investigation intent, often shortened to commercial intent, describes a search in which the person researches and compares …

HTTP compression is the process of shrinking text files such as HTML, CSS and JavaScript on the server before they travel over the network.

Consent mode is a Google feature that lets a website pass its visitors' consent choices to Google tags and SDKs, which then adjust their …

Content in SEO means everything on a website that users and search engines evaluate: text, images, video, audio and interactive elements …

A content audit is a systematic review of the content on a website to decide which pages to keep, update, consolidate or remove.

Content brief is a working document written before a text is produced.

Content decay is the gradual decline of rankings, impressions and clicks on a page that used to perform well.

Content freshness describes how current a piece of content is relative to a search query.

Content gap analysis compares a website's content with what the audience searches for and what competitors cover, to find missing or weak …

A content hub is a section of a website that gathers content on one topic or for one audience and links it together.

The Content-Language header is an HTTP header that states which language group a response is intended for.

Content marketing is a marketing approach in which a company creates and distributes useful content to attract and keep a clearly defined …

Content pruning is the deliberate review of existing pages with the goal of updating, merging or removing those that perform poorly or are …

In SEO, content quality describes how well a page serves what the searcher is looking for.

Content refresh means revising an existing page so that it matches current facts and the current search intent again.

The Content Signals Policy is a robots.txt extension that lets a site state what crawlers may do with its content after fetching it.

A content strategy is the plan behind a website's content.

Content syndication means that content you already published appears again on one or more other websites, with your permission.

The context window is all the text a language model can reference when it generates a response, including the response itself.

Conversational search is a form of search in which users ask in natural language and can follow up, while the system keeps the earlier …

A conversion is an action by a visitor that has value for the business, such as a purchase, a sign-up, an inquiry or a download.

Conversion rate is the share of visitors or interactions that lead to a conversion, expressed as a percentage.

Conversion rate optimization (CRO) is the ongoing process of increasing the share of website visitors who take a desired action, such as a …

A cookie banner is a notice through which visitors consent to or reject the storage of cookies and similar technologies.

Core Web Vitals are three metrics Google uses to describe the user experience of a web page.

Cornerstone content is the term SEOs use for the most important pages or articles of a site on a core topic.

A country code under ISO 3166-1 is a standardized identifier for a country or territory.

Crawlability describes whether a crawler such as Googlebot can reach and fetch a URL.

Crawlable links are links that a crawler can follow reliably.

Crawl budget is the amount of time and resources Google's crawlers spend on a site.

A crawl comparison puts the results of two crawls of the same website side by side.

Crawl-delay is a robots.txt directive that asks a crawler to wait between requests.

Crawl demand is the part of crawl budget that describes how much a crawler wants to crawl a site.

Crawl depth, also called click depth, is the number of link steps between a starting point and a URL.

Crawled - currently not indexed is a status in the Page indexing report of Google Search Console.

Crawler directives are instructions that tell search engine bots how to fetch and process a website.

Crawler IP ranges are the IP address blocks from which a search engine operator runs its crawlers.

Crawl errors are problems that keep a crawler from fetching a URL or a whole site, for example server errors, missing pages or failed DNS …

A crawler trap (also called a spider trap) is, in SEO, a part of a website where a crawler keeps finding new URLs that add little or no …

Crawl frequency is how often a crawler requests a website or an individual URL.

Crawling is the automated fetching of web pages by a program called a crawler.

Crawl rate is the number of requests a crawler sends to a website within a given period of time.

The Crawl Stats report is a report in Google Search Console that summarizes Googlebot's requests to a site.

The crawl-to-refer ratio (also written crawl-to-referral ratio) compares how many pages a platform crawls with how often it sends users to …

Critical CSS is the CSS needed to render the content that is visible without scrolling (above the fold).

A cross-domain canonical is a rel="canonical" link that points to a URL on a different domain.

Cumulative Layout Shift (CLS) is a Core Web Vitals metric for visual stability. web.dev defines it as the largest burst of layout shift …

A custom 404 page is the page a server shows when a requested URL does not exist, designed to help visitors continue.

The customer journey is the sequence of touchpoints a person has with a brand, from first contact through research and purchase to the …

Dark traffic means visits whose origin an analytics tool cannot determine.

A data layer is a JavaScript object on a website that holds information about the page and user interactions so that tags can read it.

data-nosnippet is an HTML attribute that marks a section of text on a page as off limits for snippets in search results.

Data sampling means that a report is calculated from a subset of the available data and the result is extrapolated.

Dead-end pages are pages where a visitor has no obvious next step, because no link or call to action leads onward.

Deduplication systems are ranking systems at Google that remove redundant results when many pages say nearly the same thing.

A deep link is a link that points directly to specific content instead of a start page.

Deep research is a feature of AI assistants that investigates a topic across many web sources in several steps and returns a longer report …

Deindexing means a URL is removed from a search engine's index and no longer shows in its results.

Deployment, also called a release, is the step in which a new version of a website goes from the development process to the live …

Diffbot is a company that uses machine learning to turn web pages into structured data.

Digital PR is public relations carried out through online channels.

A direct answer, also called an answer box, is in SEO a result element that answers a question directly on the results page or inside an …

Direct traffic is the group of website visits that analytics cannot assign to a source.

Disallow is a rule in a robots.txt file that tells a crawler not to fetch URLs whose paths begin with a given value.

Disavowing links means uploading a list of links to Google that Google should ignore when assessing your site.

Discovered - currently not indexed is a status in the Page indexing report of Google Search Console.

DNS (Domain Name System) translates domain names such as example.com into IP addresses so that browsers and crawlers can reach the right …

A dofollow link is an ordinary link that carries no rel value such as nofollow, sponsored or ugc.

The Document Object Model (DOM) is the structure a browser builds in memory from a web page.

A domain name is a text label such as example.com that identifies a host on the internet and maps, through the Domain Name System (DNS) …

Domain authority is a score that estimates how strong a website's link profile is.

Domain consolidation means merging several domains, for example country, brand or legacy domains, into one or a few.

In SEO, a domain migration means a website moves to a different domain name, for example from old-brand.com to new-brand.com, and every …

Domain popularity is, as defined by SISTRIX, the number of different domains that link to an analyzed domain at least once.

DOM size is the total number of elements in the Document Object Model of a web page, the in-memory tree the browser builds from the HTML.

Doorway page refers to a page built to rank for specific search queries that sends visitors on to a different destination.

DuckAssistBot is the web crawler DuckDuckGo uses for the AI-assisted answers in DuckDuckGo Search.

DuckDuckBot is the web crawler of the DuckDuckGo search engine.

Duplicate content is identical or very similar content that can be reached at more than one URL, either within one website or across …

Dwell time is, in SEO usage, the time between a click on a search result and the return to the results page.

Dynamic rendering is, in the SEO sense, a setup in which a server detects crawlers and serves them a server-rendered HTML version, while …

Dynamic serving is a mobile configuration in which one URL returns different HTML depending on the device.

A dynamic URL contains parameters that the server evaluates before it returns the page, for example /product?id=12&color=red.

Ecommerce replatforming (also called shop migration) is the move of an online store from one commerce platform to another, for example …

E-commerce SEO is search engine optimization for online stores.

Edge SEO, also called serverless SEO, means, according to Patrick Stox, making technical SEO changes at the CDN or in an edge worker …

An editorial calendar is a schedule that lists which content gets published, on which date, in which channel and who is responsible for it.

An editorial link is a link that an editor or site owner places in an article on their own initiative because the linked content helps …

E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness.

Vector embeddings are lists of numbers that represent data such as words, sentences, documents, images or audio as points in a vector space.

Engagement rate in Google Analytics 4 is the percentage of sessions that were engaged.

Enterprise SEO is search engine optimization for large organizations.

In SEO, an entity is a uniquely identifiable thing, such as a person, organization, place, product or concept, that search engines can …

An entry page is the first page of a visit in web analytics.

An ETag (entity tag) is an HTTP response header that identifies a specific version of a resource.

The EU AI Act is Regulation (EU) 2024/1689, the European Union's rules for artificial intelligence.

Event schema is structured data that describes an event, such as a concert or workshop.

Event tracking is the measurement of individual interactions on a website or in an app, such as link clicks, file downloads, video plays …

Evergreen content is content that stays relevant over a long period, so people keep searching for and reading it.

An exact match domain (EMD) is a domain name that consists exactly of a search phrase, for example dental-insurance-compare.com.

The exact match domain update (EMD update) is a Google change from late September 2012 that reduced the ranking advantage of domains whose …

An expired domain is a domain whose registration ran out because its previous owner did not renew it.

Expired domain abuse is a Google spam policy violation.

Faceted navigation is a filter system that lets visitors narrow a list of products or content by several attributes at once, such as …

A fake Googlebot is a client that identifies itself as Googlebot in the user agent but does not come from Google.

A false positive (false alarm) is an alert that reports a problem that is not there.

An FAQ page (FAQ stands for "frequently asked questions") collects questions customers often ask about a product, service or topic and …

FAQ schema, also called FAQPage markup, is a schema.org type that describes a page with a list of frequently asked questions and their …

A favicon (favorite icon) is the small icon of a website.

The favicon in search results is the small icon Google shows next to the site name and URL of a result.

A featured snippet is a highlighted answer box in Google Search.

fetchpriority is an HTML attribute that tells the browser how important a resource is compared to other resources of the same type.

Field data is performance data collected from real visitors on their own devices and networks.

Filter pages, in online shop SEO, are category or list pages that get their own URL after a visitor selects filters such as color, size or …

Fine-tuning in AI means continuing the training of an already pretrained model on additional, task-specific examples.

First Contentful Paint (FCP) is a performance metric for the time between the start of navigation and the moment the first piece of …

First Input Delay (FID) was a Core Web Vitals metric.

The Florida update is the SEO industry's name for a major change in Google's ranking that began on November 16, 2003.

Focused crawling is a crawling strategy that fetches only pages relevant to a specific topic instead of covering the whole web.

Footer links are links in the footer of a website.

A fragment identifier is the last part of a URL, starting with the # character.

Fred is the unofficial name of a Google ranking update from March 2017.

Free product listings let merchants show products on Google without paying for ads.

Fresh crawl and deep crawl are historical terms from Google's early years.

Gated content is content that visitors can only access after a step such as filling in a form with a name and email address.

Generative AI refers to AI models that create new content such as text, images, audio, video or code.

A GEO audit is a review of whether and how a website appears in answers from AI systems such as ChatGPT, Gemini or Google AI Overviews …

GEO (generative engine optimization) is the practice of making content more likely to appear in answers from generative AI systems such as …

Geo-targeting means directing content or ads at users in a specific location.

A go-live is the point at which a system or website moves from testing into production, so real users can reach it.

In SEO, a Google algorithm update is a change to the algorithms and ranking systems of Google Search that affects how results are ordered.

Google Analytics 4 (GA4) is the current version of Google Analytics, Google's analytics service for websites and apps.

The Google API leak is the 2024 publication of internal documentation for Google Search's Content Warehouse API.

Google Autocomplete is the feature in Google Search that shows predicted queries in a dropdown while someone types.

Google bombing (also Googlebomb) was an attempt to push a page up for a search term by pointing many links with identical anchor text at …

Googlebot is the web crawler of Google Search.

Googlebot Smartphone is the mobile version of Googlebot, Google's crawler for Search.

Google Business Profile (formerly Google My Business) is the free business listing that appears in Google Search and Google Maps.

Google cache was a Google Search feature that showed the copy of a page Google had stored.

Google Caffeine is the name of a web indexing system that Google announced in June 2010.

Google-CloudVertexBot is a Google crawler that fetches a website when the site owner has requested it, to build Vertex AI agents.

A Google core update is a broad change to the algorithms and systems of Google Search that Google rolls out several times a year.

Google Dance is a historical SEO term for the noticeable ranking changes that followed Google's index updates in the early 2000s.

Google Discover is part of Google Search that shows people content related to their interests, based on their Web and App Activity …

Google-Extended is a robots.txt product token that lets site owners control whether content Google has crawled may be used for training …

Google for Jobs is the common name for the job search experience in Google Search.

Google Images is Google's image search.

The Google Indexing API is an interface that lets site owners notify Google directly when a page is added, updated or removed.

Google-InspectionTool is a Google crawler used by testing tools for Search, including the Rich Results Test and the URL Inspection tool in …

Google Lens is Google's visual search.

Google Maps SEO is the work of making a business easier to find in Google Maps and the local pack.

Google Merchant Center is the free tool in which retailers manage their product data for Google.

Google News is a Google service that collects current news from many sources and presents it by relevance, freshness and the user's …

GoogleOther is a generic crawler from Google that product teams can use to fetch publicly accessible content.

Google Publisher Center is Google's admin tool for news publishers.

Google Safe Browsing is a Google security service that warns users about dangerous sites and files.

Google sandbox is an SEO theory that Google holds back new websites in search results for a while, even when their content and links are …

Google Search Central is Google's official source of guidance for people who build and maintain websites for Google Search.

Google Search Console is a free service from Google that shows site owners how their website performs in Google Search.

Google Search Essentials is the name of Google's guidelines for websites in web search.

The Google Search Status Dashboard is a status page where Google reports widespread issues and ranking updates affecting Google Search.

Google Shopping is the area of Google where products from retailers appear with image, price and store.

Google Tag Manager (GTM) is a tag management system.

Google Trends is a free Google tool that shows how interest in a search term changes over time.

GPTBot is OpenAI's web crawler for collecting publicly available content that may be used to train its generative AI models.

Grey hat SEO is industry slang for optimization tactics placed between white hat SEO (within search engine guidelines) and black hat SEO …

Grounding in AI means tying a language model's answer to external, checkable sources instead of relying on training data alone.

A grounding page is a web page that states verifiable facts about one entity, such as a company, person or product, in plain language and …

Grounding with Google Search is a tool in the Gemini API.

A GTIN (Global Trade Item Number) is a globally unique number that identifies a product, usually shown as the barcode on its packaging.

A guest post is an article that an outside person or company writes for another website or blog.

A hacked site is a website on which third parties have placed content, code or redirects without permission.

Hash URLs with #!, also called hashbang URLs, are an address form from the early AJAX era in which a JavaScript application stores the …

Heading hierarchy is the outline of a page built from the HTML elements <h1> to <h6>.

Headings (H1–H6) are the HTML elements <h1> through <h6> that name and structure the sections of a web page.

A headless browser is a web browser that runs without a visible user interface and is controlled through code or the command line.

A headless CMS is a content management system that stores and manages content and delivers it through an API, without producing web pages …

Heatmap (or heat map) is a visualization that uses color to show values: warm colors mark high values, cool colors low ones (Coursera).

Helpful content is content that Google describes as created primarily to benefit people rather than to attract search traffic.

The helpful content update was a Google ranking system announced in August 2022 to show more original, helpful content written by people …

Hidden text is content placed on a page so that visitors cannot see it, or barely see it, while search engines can still read it.

The Hilltop algorithm is a ranking method from search engine research that scores pages according to the links of independent "expert …

The History API is a browser interface through which JavaScript reads and changes the session history of a tab.

Holistic content is an SEO term for content that treats a topic comprehensively and covers the different questions and angles searchers …

Homepage is the page at the root of a domain or subdomain, for example https://example.com/.

Google Search is a fully automated search engine that uses software called web crawlers to find pages for its index.

HowTo schema is a schema.org type for instructions that lead to a result in a sequence of steps.

hreflang is an attribute that tells search engines which language or regional versions of a page exist.

A hreflang return tag means two pages reference each other through hreflang.

hreflang in an XML sitemap is one of three ways to tell Google about language and country versions of a page.

HSTS (HTTP Strict Transport Security) is a security mechanism that tells browsers to access a host only over HTTPS for a set period.

.htaccess is a plain-text configuration file for the Apache web server.

HTML (HyperText Markup Language) is the markup language that defines the meaning and structure of web content.

The HTML head, written as the <head> element, holds machine-readable metadata about a document.

The HTML lang attribute declares the human language of an element's content.

An HTML sitemap is an ordinary page on a website that lists links to its content so visitors can find their way around.

HTML validation, often called W3C validation, checks whether a page's markup follows the rules of the HTML specification.

HTTP/2 is the second major version of the HTTP protocol, standardized in RFC 9113 (the current revision, which replaces RFC 7540).

HTTP/3 is the third major version of the HTTP protocol, standardized as RFC 9114 in June 2022.

An HTTP header is a name-value pair that a client or server sends along with an HTTP request or response to pass extra information, such …

The HTTP Link header is a response header that expresses links between resources, with the same meaning as the HTML <link> element.

HTTPS (Hypertext Transfer Protocol Secure) is the HTTP protocol sent over an encrypted TLS connection.

An HTTP status code is the three-digit number a web server sends with every response.

An HTTP to HTTPS migration moves a website from unencrypted HTTP to HTTPS.

A hub page is, in SEO, a page that collects links to the content on one topic.

humans.txt is a text file in the root of a website that names the people who built it, such as developers, designers and writers.

In SEO, Hummingbird is a major improvement to Google's ranking systems from 2013, not a bird or an app.

Hydration is the step in which JavaScript in the browser attaches event handlers and application state to HTML that a server already …

An iframe (inline frame) is an HTML element that embeds another HTML document in the current page, for example a video player, a map or a …

An image file name is the name of the image file on the server, such as red-running-shoe.jpg.

An image pack is, in SEO terminology, a block of image results inside the regular Google web results.

Image SEO (image optimization) is the set of practices that help images appear in Google Search and Google Images while keeping page load …

An image sitemap is an XML sitemap that gives Google additional image URLs for a page.

Impressions in SEO are the number of times a link to your website was shown in Google Search results.

Incremental static regeneration (ISR) is a caching strategy that serves pre-rendered static pages and regenerates them in the background …

Indexability describes whether a URL is technically allowed to be added to a search index.

In SEO, index bloat means a website has many more URLs in a search engine's index than are useful for searchers.

Index coverage is the indexing status of the URLs of a site in Google Search Console.

Indexed pages are URLs that Google has crawled, processed and added to its index.

indexifembedded is a robots rule that lets Google index the content of a page when that content is embedded in another page through an …

Indexing, in SEO, is the step in which a search engine analyzes a crawled page and stores it in its index, the database it draws search …

IndexNow is an open protocol that lets a website tell participating search engines which URLs were added, updated or deleted, so crawlers …

Infinite scroll is a design pattern where new content loads automatically as a visitor scrolls down, so there is no click to a second page.

Informational intent describes a search in which the person wants to learn something, such as a definition, an explanation, or instructions.

Information retrieval (IR) is finding material, usually documents, of an unstructured nature, usually text, that satisfies an information …

Instant Checkout was a ChatGPT feature that let users buy products without leaving the chat.

Interaction to Next Paint (INP) is a Core Web Vitals metric for how quickly a page responds.

Internal linking is the set of links that point from one page of a website to another page on the same website.

International SEO is the optimization of a website for users in several countries or languages.

Intrusive interstitials are page elements that obstruct the view of the content, usually for promotional purposes, according to Google.

An IP address is a numeric label that identifies a device or server in a network that uses the Internet Protocol, and it tells other …

IPv6 (Internet Protocol version 6) is the successor of IPv4 and is specified in RFC 8200.

JavaScript frameworks such as React, Angular, and Vue are toolkits for building interactive web interfaces from reusable components.

A JavaScript redirect is a redirect that the browser carries out with a script, usually by setting window.location.

JavaScript SEO is the work of making sure search engines can crawl, render, and index content, links, and metadata that a page creates or …

JobPosting schema is structured data that describes a job opening.

JSON-LD (JSON for Linked Data) is a JSON-based format for embedding structured data in a web page.

Key moments are segments of a video that Google Search shows with a timestamp and a label, so users can jump straight to the part they need.

In SEO, a keyword is a word or phrase that people type into a search engine and that a page is meant to be found for.

Keyword cannibalization happens when several pages of the same website target the same search query or intent and, according to reports …

Keyword clustering is the grouping of related search terms into sets that share the same search intent, so that one page can target a …

Keyword density is the percentage of times a keyword or phrase appears on a page compared to the total number of words.

Keyword difficulty (KD) is a score from 0 to 100 that an SEO tool assigns to a keyword to estimate how hard it is to rank in the top 10 …

A keyword gap is the set of search terms that competitors rank for but your own website does not.

Keyword mapping is the process of assigning target keywords to specific pages of a website and recording those decisions in a document …

Keyword proximity is the distance between the words of a search phrase within a text, counted as the number of words that separate them.

Keyword research is the process of finding out which words and phrases people type into search engines when they look for a topic …

Keyword seasonality means that the number of searches for a term rises and falls in a recurring pattern during the year.

Keyword stuffing is the practice of filling a web page with keywords or numbers to manipulate rankings in Google Search results.

The knowledge cutoff is the point in time up to which a language model has been trained on data.

The Knowledge Graph is Google's database of entities, such as people, places, organizations, and things, and the relationships between them.

A knowledge panel is an information box in Google Search that gives a quick snapshot of a person, place, organization or other entity that …

A landing page is a page that visitors reach after clicking an ad, an email link or a search result and that is built around one goal …

A language code, in web and SEO use, is a short identifier for a language, usually the two-letter code from ISO 639-1 such as de, en or fr.

A large language model (LLM) is an AI model trained on very large amounts of text that generates language by repeatedly predicting the …

Largest Contentful Paint (LCP) is a Core Web Vitals metric for loading speed.

lastmod is an optional field in an XML sitemap that states when the content of a URL last changed.

The Last-Modified header is an HTTP response header with the date and time the server believes a resource was last changed.

Latent semantic analysis (LSA) is a statistical technique from natural language processing.

Lazy loading means that non-critical resources such as images, iframes or scripts load only when they are needed, for example when they …

Lemmatization is a natural language processing technique that reduces inflected word forms to their dictionary form, the lemma.

Lighthouse is, in the web context, an open-source, automated tool from Google that audits the quality of web pages.

Link attributes, in an SEO context, are values of the rel attribute on an <a> element that describe how a link relates to its target.

Linkbait (also link bait) is content designed so that other sites want to link to it.

Link building is the practice of getting other websites to link to yours.

Link juice (also called link equity) is an informal SEO term for the value a link is thought to pass from the page it sits on to the page …

A link exchange, also called reciprocal linking, means two websites agree to link to each other.

A link farm is a group of websites that mainly exist to link to each other or to chosen target pages and so lift their rankings …

Link popularity describes how many incoming links a page or domain has.

A link profile, also called backlink profile, is the full set of external links pointing to a website or its pages.

Link reclamation means restoring backlinks that have disappeared or stopped working.

Link rot is the gradual decay of hyperlinks over time.

A link scheme is a pattern for creating links mainly to influence search rankings.

In SEO, link spam means links to or from a site that exist primarily to manipulate search rankings.

A link spam update is an announced improvement to how Google detects and discounts unnatural links.

Link velocity is the rate at which a website or page gains new backlinks in a given period, usually counted as new links or new referring …

llms-full.txt is a file that makes the complete text of a website or documentation available in one Markdown document.

llms.txt is a proposed Markdown file at the root of a website (/llms.txt) that gives language models and AI agents a short, curated …

LLM web search is a tool function that lets a large language model run web searches while it answers a request, read the results, and cite …

LocalBusiness schema is structured data from schema.org that describes a local company or branch in a machine-readable way. schema.org …

Local citations are mentions of a business that include its name, address and phone number (NAP), with or without a link to its website.

Locale-adaptive redirects send visitors to a particular language or country version based on IP address, location or browser language.

The local pack (also map pack or 3-pack) is the block in Google Search that shows a small set of local businesses next to a map when a …

Local SEO (local search engine optimization) covers the work that makes a business visible in searches with a geographic component, such …

Location pages are pages on a website that each cover one location or branch of a business.

A log file is a record that a system writes automatically while it runs.

Log file analysis in SEO means evaluating a web server's access logs, which record every request for a URL with its timestamp, status …

A long-tail keyword is a specific search query with low search volume, usually made up of several words.

Lost backlinks are links that a backlink tool found before and does not find any more.

LSI keywords is an SEO term for words that relate to a main keyword, such as synonyms and neighboring concepts.

Maintenance mode (SEO meaning: a website temporarily shows a notice page while work is done) should answer with HTTP status 503 Service …

A manual action is a penalty Google applies to a site after a human reviewer determines that pages do not comply with Google's spam …

The manufacturer part number (MPN) is the identifier a manufacturer assigns to a product or part.

A Markdown version for LLMs is a second, leaner version of a page in Markdown that AI agents and language models can request instead of …

Marketplace SEO is the optimization of product listings for the internal search and rankings of a marketplace such as Amazon or eBay.

max-image-preview is a robots rule that sets the largest size in which Google may show an image from a page as a preview.

max-snippet is a robots rule that sets the maximum length of a text snippet in search results, counted in characters.

MCP (Model Context Protocol) is an open standard that lets AI applications such as Claude or ChatGPT connect to external data sources …

An MCP server is a program that exposes capabilities such as functions, data and prompt templates to AI applications through the Model …

The Medic update is the name the SEO industry uses for a Google core update from August 2018.

A mega menu is a website navigation element that opens a large panel with many links, usually grouped in columns, when a visitor hovers …

Merchant listings are Google Search experiences for products that shoppers can buy directly on a page.

A meta description is an HTML meta tag that summarizes a page's content in one or two sentences.

Meta-ExternalAgent is a web crawler run by Meta, the company behind Facebook, Instagram and WhatsApp.

Meta-ExternalFetcher is a Meta user agent that fetches individual links when a user asks for them.

The meta keywords tag is a meta element in the <head> of a page where site owners once listed keywords for the page.

Meta refresh is an HTML <meta http-equiv="refresh"> tag that tells the browser to reload the page or load another URL after a set number …

The meta robots tag is an HTML element in the <head> of a page that tells search engines how to handle that page.

A metasearch engine sends a query to several other search engines at once and merges their results into one list.

Meta tags are meta elements in the <head> of an HTML page.

Meta-WebIndexer is a Meta crawler that, according to Meta, navigates the web to improve the quality of search results in Meta AI.

Microdata is a syntax from the HTML standard for marking up content as structured data directly in the visible HTML.

A mid-tail keyword is a search term between broad short-tail and specific long-tail keywords.

Minification is the process of removing unnecessary or redundant data from a resource without changing how the browser processes it (MDN).

A mirror site is a replica of a website hosted on a different server under a different URL.

MistralAI-User is a user agent from Mistral AI that visits a web page when a person asks Mistral's assistant a question.

Mixed content occurs when a page loaded over HTTPS includes resources, such as images, scripts or stylesheets, that are fetched over …

Mobile-first indexing means that Google uses the mobile version of a site's content, crawled with the smartphone user agent, for indexing …

Mobile-friendliness describes how easy a website is to read and use on a smartphone.

Mobilegeddon is the SEO nickname for Google's mobile-friendly update, which began rolling out globally on April 21, 2015.

A money keyword, according to reports from SEO practice, is a search term that is closely tied to a purchase intent, so ranking for it …

A multilingual website offers its content in more than one language.

Multimodal search is search that accepts and combines more than one type of input, for example a photo and a text question.

A multiregional website explicitly targets users in different countries, for example Germany, Austria and Switzerland.

MUM (Multitask Unified Model) is an AI system from Google that can both understand and generate language.

NAP stands for name, address and phone number.

A natural link is a link that a site owner places on their own because the linked content seems useful to their readers.

NavBoost is a Google ranking signal that pairs search queries with documents by memorizing which results users clicked.

Navigational intent describes a search in which the person wants to reach a specific website or page and uses the search engine as a …

Near-duplicate content is the SEO term (general usage, not a Google definition) for pages whose content is very similar to other pages …

Near me searches are queries that ask for something close to the searcher, such as "pharmacy near me", without naming a place.

Negative SEO means deliberate attempts to harm the search rankings of another website.

Neural matching is an AI system Google uses to understand representations of concepts in queries and pages and to match them.

A news sitemap is an XML sitemap with extra details for news articles.

A niche keyword is a specific search term for a narrow topic or a small audience.

NLP here means natural language processing, a field of artificial intelligence that lets computers read, interpret and generate human …

NLWeb (Natural Language Web) is an open project that gives websites a natural language interface for people and AI agents.

noarchive is a robots rule that used to stop Google from showing a cached link to a saved copy of a page in search results.

nofollow is a value that tells search engines not to follow a link or all links on a page.

noimageindex is a robots rule that tells Google not to index the images on the page where it appears.

noindex is a rule that tells search engines not to show a page or file in their search results.

nosnippet is a robots rule that tells a search engine not to show a text snippet or video preview for a page.

OAI-SearchBot is a crawler run by OpenAI.

Offer markup is structured data of the schema.org type Offer.

Off-page SEO covers activities and signals outside your own website that affect how a site performs in search.

Online reviews are customer ratings of a business or product, shown in Google as stars with text.

On-page SEO covers all optimizations made directly on the pages of your own website, including content, HTML elements, structure and …

OpenAPI is a language-agnostic specification format for describing HTTP APIs.

Open Graph is a protocol that defines how a web page is displayed when it is shared on social networks or in messaging apps.

Organic search refers to the results a search engine ranks on its own and that nobody pays to place.

Organic traffic is the visits to a website that come from unpaid links in search results.

Organization schema is structured data that describes an organization, such as its name, URL, logo and contact details.

Original content systems are ranking systems that Google uses to show original content, including original reporting, ahead of pages that …

An orphan page is a URL on a website that no other page of the same site links to.

Outbound links, also called external links, are links that point from a page to a different domain.

Out-of-stock products are items a shop cannot currently deliver while the product page still exists.

Outreach in SEO means contacting site owners, bloggers or editors to present content and earn backlinks, mentions or guest posts.

Over-optimization in SEO describes optimization that is pushed so far that it looks manipulative.

Page Authority (PA) is a metric from the SEO tool vendor Moz.

Page experience is Google's term for the signals that show how pleasant a page is for visitors.

PageRank is a method for scoring the importance of a web page from the links that point to it.

PageRank sculpting is a historical SEO tactic.

Page speed is how quickly a web page loads, becomes visible, and responds to user input.

PageSpeed Insights (PSI) is a free Google tool that analyzes the performance of a web page on mobile and desktop and suggests improvements.

A page template is the layout and code from which many pages of the same type are generated, such as product pages, category pages or …

Pageviews count how often pages of a website were viewed.

Pagination on the web splits a long list across several numbered pages, such as the products of a store category, blog archives, or search …

The Panda update was a Google system introduced in 2011 to make sure high-quality and original content appears in search results.

A partial match domain (PMD) is a domain name that contains part of the keywords a site wants to be found for, combined with other words …

Passage ranking is an AI system Google uses to identify individual sections, called passages, of a web page to better understand how …

Password protection, in the website sense, means locking a site or directory behind a username and password, most often with HTTP Basic …

The Payday Loan update is a Google webspam update that, according to reports, began in June 2013 and affected queries with heavy spam …

Pay per crawl is a model in which a crawler pays for each page it fetches.

Paywalled content is content that is fully visible only after payment, subscription or registration.

PDF SEO covers measures that help PDF files appear in search results and display sensibly.

The Penguin update was a Google system introduced in 2012 to combat link spam.

People Also Ask (PAA) is a block in Google's search results with expandable questions related to the search.

People-first content is content written for people with a specific need and judged by how useful it is to them.

The performance report is the report in Google Search Console that shows how often a website appeared in Google Search results and how …

PerplexityBot is the crawler of the AI search engine Perplexity.

Perplexity-User is a Perplexity user agent that visits web pages when a person asks Perplexity a question and the answer needs a page.

Personalized search means that a search engine adjusts results for the person searching.

Phantom update is the SEO industry's name for a change in Google's ranking from early May 2015, often called "Phantom 2".

The Pigeon update is, according to reports, the name Search Engine Land gave to a change in Google's local search that launched in the …

A pillar page is a comprehensive page on a broad topic that links to more detailed pages and is linked back from them.

Pixel width is the horizontal space a title or meta description takes up in a search result.

Pogo-sticking in SEO is the behavior of clicking a search result, returning to the results a few seconds later and clicking another result.

Possum update is the name the local SEO community gave to a change in Google's local ranking around September 2016.

Preferred sources is a Google Search feature that lets signed-in users pick the news sites they want to see more often.

Preload, preconnect and prefetch are resource hints.

Prerendering means rendering a page ahead of time instead of when someone requests it.

A private blog network (PBN) is a group of websites under common control whose main purpose is to link to one or more target sites to …

A product description is the text on a product detail page that explains what an item is, what it does and how it is used.

A product detail page (PDP) is the page of an online store that presents one product with its information and the option to buy.

A product feed is a file or interface that lists a shop's products with attributes such as ID, title, link, image, price and availability.

Product schema is schema.org structured data that describes a product on a web page, for example its name, image, price and availability.

Product snippets are search results that include extra product information such as ratings, review details, price and availability.

A product variant is a version of one product that differs in an attribute such as size, color, material or pattern.

Programmatic SEO is the automated creation of many pages from structured data and a page template, for example one page per city, per …

A progressive web app (PWA) is an app built with web technologies that can be installed and used like a platform-specific app, partly even …

In AI use, a prompt is the text input a user gives an AI model to get a response.

Prompt tracking is the regular running of defined prompts on AI systems and the evaluation of the answers for brand mentions, linked …

Prompt volume is an estimate of how many prompts people send to AI assistants such as ChatGPT about a topic.

Query Deserves Freshness (QDF) refers to the freshness systems Google uses to show newer content for queries where people would expect it.

Query fan-out is a technique used in AI search in which the system breaks one question into several related sub-queries and runs them at …

The query string is the part of a URL that starts with a question mark (?) and carries additional data as key and value pairs.

Question keywords are search queries phrased as a question, usually starting with a word such as who, what, when, where, why or how.

RankBrain is an AI system in Google Search that helps Google understand how words relate to concepts.

Ranking in SEO is the order in which a search engine such as Google lists results for a query.

A ranking drop is a fall in the position of a page in search results for one or more queries.

Ranking factors are the signals search engines use to order pages for a query.

A ranking position is the place at which a page appears in a search engine's results for a given query, counted from the top.

Rank tracking is the regular measurement of where a website appears in search results for a defined set of keywords.

Rate limiting controls how many requests a client may send to a server or API within a set time.

Raw HTML is the source code of a web page as the server delivers it in the HTTP response, before a browser or crawler has run any …

RDFa (Resource Description Framework in Attributes) is a W3C standard for adding structured data to a page through extra attributes in the …

RDF (Resource Description Framework) is a W3C data model that describes information as statements made of a subject, a predicate, and an …

Readability describes how easily readers can understand a written text.

Real user monitoring (RUM) collects performance data from real visits to a website or app, using code that runs in the visitor's browser.

Recipe schema is structured data that describes a cooking recipe, such as ingredients, times and instructions.

A reconsideration request asks Google to review a manual action taken against your website and lift it.

A recrawl is a crawler fetching a URL it already knows again so that changes reach the index.

A redirect sends browsers and crawlers that request one URL automatically to a different URL.

A redirect chain is a sequence of two or more redirects between the requested URL and the final page, for example A to B to C. A single …

A redirect loop exists when URLs redirect to each other in a circle, for example A to B and B back to A. The target page is never reached …

Redirect mapping is the planning of redirects for a relaunch, domain move or migration.

Referral traffic is the group of visits that reach a website by clicking a link on another website.

The referrer is the address of the page from which a visitor reached the current page.

A referring domain is a domain that links to a given website or page at least once.

A regular expression (regex) is a text pattern that describes a set of strings.

rel=next and rel=prev are link relations that mark a page as part of a series and point to the following and preceding page, for example …

rel="sponsored" is a value of the rel attribute on links.

rel="ugc" is a value of the rel attribute on links.

Related searches are query suggestions that Google shows on a results page so people can refine or continue their search.

Reliable information systems is an umbrella term from Google's overview of ranking systems.

The Removals tool in Google Search Console lets site owners temporarily hide their own URLs from Google Search results.

Render-blocking resources are files, mostly CSS and JavaScript, that the browser has to load and process before it can display page content.

Rendered HTML is the markup of a page after JavaScript has run, in other words the current state of the DOM.

In SEO and web development, rendering is the process in which a browser or crawler turns HTML, CSS, and JavaScript into the finished page …

The rendering queue is, in SEO, the waiting list where Google places crawled pages until it renders them with JavaScript.

Request indexing is a function of the URL Inspection tool in Google Search Console that asks Google to crawl a single URL.

Responsive design is a web design approach in which one URL and one HTML document serve every device, while CSS adapts the layout to the …

Retrieval-augmented generation (RAG) is a method in which a language model retrieves relevant information from an external source before …

Return policy markup (MerchantReturnPolicy) is structured data that describes a store's return conditions in a machine-readable way.

A reverse DNS lookup (rDNS) is a DNS query that finds the hostname belonging to an IP address.

Review schema is structured data that describes a review or an aggregate rating of an item.

The reviews update (first called product reviews update) was a series of announced changes to Google's reviews system, which rewards …

Rich results are Google search results that show more than a title, URL, and description, such as ratings, prices, images, or recipe …

The Rich Results Test is a Google tool that shows which rich results can be generated from the structured data on a page.

Rich snippets are search results that show more than title, URL, and description, for example star ratings, prices, or images.

The Robots Exclusion Protocol (REP) is the standard that lets site owners tell crawlers, through a robots.txt file, which parts of a site …

robots.txt is a plain text file at the root of a host that tells crawlers which URLs they may request.

robots.txt monitoring is the regular, automatic check of a website's robots.txt for changes and errors.

A rollback returns a system to an earlier, working state.

An RSS feed or Atom feed is an XML file that lists the latest content of a website in a machine-readable form, usually with title, link …

sameAs is a schema.org property that points to a URL of a reference web page that unambiguously identifies an item. schema.org gives the …

Scaled content abuse is a Google spam policy violation.

The Schema Markup Validator (validator.schema.org) is a tool for checking structured data that uses the schema.org vocabulary.

Schema.org is a shared vocabulary for describing the content of a web page to machines.

Scraped content is text, images, or data taken from other websites, often automatically, and republished elsewhere.

A search algorithm is the set of rules a search engine uses to select pages for a query and put them in order.

The Search Console API is the programming interface of Google Search Console.

The Search Console bulk export is a Google feature that schedules a daily export of a property's performance data to BigQuery, Google's …

Search Console Insights is a report in Google Search Console that summarizes key metrics and traffic changes of a site in a simplified form.

A Search Console property defines which URLs a site owner sees data for in Google Search Console.

A search engine is a program that finds documents for a query and sorts them by estimated relevance.

Search engine submission means registering a website with a search engine so that it appears in results.

Search everywhere optimization is a marketing term for making content findable wherever people search, not only on Google.

A search index is the database in which a search engine stores what it has learned about the pages it crawled.

Search intent (also user intent) is the goal a person has when typing a query into a search engine.

Search operators are characters and keywords, such as quotation marks or site:, that narrow a query in a search engine.

The Search Quality Rater Guidelines are Google's public handbook for the people who evaluate search results and web pages on its behalf …

A search query is the input a person gives a search engine to find information, usually typed words, but also spoken questions or images.

In SEO, a search snippet is the short description shown below the title link of a search result.

Search visibility (also SEO visibility) describes how often and how prominently a website appears in search results for relevant queries.

Search volume is an estimate of how often people search for a term in a search engine, usually given as an average per month for one …

security.txt is a plain text file in which an organization states how to report security vulnerabilities on its website.

A seed keyword is a short, broad term that a keyword research process starts from.

A self-referencing canonical is a rel="canonical" link whose target is the URL of the page it sits on.

Semantic HTML means choosing HTML elements by what they mean instead of how they look.

Semantic search is a search method that interprets the meaning and intent of a query and returns results that match that meaning, even …

The Semantic Web is the W3C's concept of a web in which data is described in a way machines can process, so it can be shared and reused …

SEM stands for search engine marketing, meaning the promotion of a website through search engines.

SEO A/B testing (also called SEO split testing) checks whether a change affects organic search performance.

An SEO audit, also called an SEO analysis, is a systematic review of a website that checks how well search engines can crawl, index, and …

An SEO competitor analysis is the process of examining how other websites perform in search results for the topics you target, in order to …

An SEO dashboard is a single view that collects key metrics of organic search, usually as charts and tables updated from connected data …

An SEO-friendly URL (also called a clean or readable URL) is an address that uses readable words to describe the page, so people and …

SEO governance describes the rules, roles and checks an organization uses to keep SEO requirements in place while many teams change the …

An SEO issue is a problem or weakness on a website that an audit or crawling tool detects, such as a broken link, a missing title or a …

SEO KPIs (also called SEO metrics when no goal is attached) are measurements that show whether search optimization is reaching a defined …

SEO localization adapts a page to a specific market so that it can be found there.

SEO monitoring, in common usage, is the ongoing, automated tracking of the factors that determine a website's visibility in search engines.

SEO QA (quality assurance for SEO) is the systematic check of changes to a website for effects on search visibility.

SEO reporting is the regular summary of search performance for a website: how visible it is in search, how much traffic and how many …

SEO ROI is the return on investment of search engine optimization: the revenue attributed to organic search, minus the cost of SEO …

SEO (search engine optimization) is the work of improving a website so it is found more often in the unpaid, organic results of search …

SEO segmentation is the practice of splitting a website's URLs or keywords into groups that share a characteristic, so that each group can …

SEO silo (siloing) means grouping a website's pages by topic into separate sections, usually through URL folders and internal links that …

An SEO strategy is the plan that defines how a website will improve its visibility in search.

Separate mobile URLs are a mobile setup where desktop and phone visitors receive different HTML at different URLs, usually on a subdomain …

A SERP analysis is the review of the search engine results page for a keyword.

SERP features are elements on a search engine results page that go beyond the standard text links.

SERP stands for search engine results page, the page a search engine such as Google or Bing shows in response to a query.

SERP volatility describes how much the results on search engine results pages change over a period of time.

Server configuration, in an SEO context, means the settings of a web server such as nginx or Apache that decide how requests are answered.

Server response time is the time a server needs to answer a request.

Server-side rendering (SSR) means the server generates the HTML of a page when a request arrives and sends the finished markup to the …

A service area business (SAB) is a business that visits or delivers to customers directly and does not serve customers at its own address.

A session ID in a URL is an identifier that links requests to one visitor session and is appended to the address, for example ?sid=a1b2c3.

A session is a period in which a user interacts with a website or app, grouped into one visit for analysis.

Severity is the level that describes how large the impact of a problem is.

The shadow DOM is an encapsulated subtree of the DOM that is attached to a regular element on a page.

Share of voice (SOV) is a marketing metric that shows how much of the visibility or conversation in a market a brand holds compared with …

Shipping details markup is structured data that states shipping costs, delivery times and destinations in a machine-readable way.

A short-tail keyword is a broad search term, usually one to three words long, that covers a whole topic.

A single-page application (SPA) is a web app that loads a single HTML document and then updates the content with JavaScript when another …

Site architecture (also called website structure or information architecture) describes how the pages of a website are grouped, named and …

Site diversity is a Google ranking system that generally keeps more than two listings from the same site out of the top results.

A site health score is a single value, usually a percentage, that an SEO audit tool calculates from the issues it finds on a website.

Sitelinks are links from the same domain that Google groups under a text result.

The sitelinks search box was a search field that Google could show under the result for a brand's homepage, letting people search within …

A sitemap index is an XML file that lists several individual sitemaps.

Sitemap monitoring is the regular, automatic check of a website's XML sitemaps.

A site name is the name Google shows for a whole website in search results, separate from the title link of each page.

Site reputation abuse, often called parasite SEO, is the practice of publishing third-party pages on an established site to take advantage …

Site search (also on-site search or internal search) is the search function inside a website or online store.

Sneaky redirects send users, search engines, or both to content they did not expect, or show users and search engines different content.

Social signals are interactions with content on social networks, such as likes, shares, comments or follower counts.

A soft 404 is a URL that returns a success status code (usually 200) while its content looks like an error page or an empty page.

Sort parameters are URL parameters such as ?sort=price-asc that change the order of items on a list page without changing which items …

SpamBrain is Google's AI-based spam-prevention system.

Spam policies are Google's rules about which techniques count as spam because they deceive users or manipulate Search systems.

A spam update is a Google improvement to its automated spam detection, in the context of search rankings.

The Speculation Rules API lets a web page tell the browser which URLs a visitor will probably open next.

Speed Index is a lab metric for page speed.

An SSL/TLS certificate is a digital file that binds a public key to a domain name, so that a browser can check it is talking to the right …

A staging crawl is a crawl of the staging or development version of a website, run before the new version goes live.

A staging environment (also called a dev or test environment) is a copy of a website or application where changes are tested before they …

Static site generation (SSG) means a site's HTML files are created once when the site is built, not when a visitor requests a page.

A static URL is an address without parameters, for example /shoes/sneakers.

Stemming is a method that reduces inflected or derived words to a common stem, so that "fishing," "fished" and "fisher" are all treated as …

Striking distance keywords are search queries for which a page already ranks, but too low to earn many clicks.

Structured data in SEO is machine-readable code on a page that states what the page is about, for example a product with its price, a …

A subdirectory (also called a subfolder) is a section of a website that sits in the path of the same domain, for example example.com/blog/.

A subdomain is a name placed in front of a domain, separated by a dot, for example blog in blog.example.com.

A system prompt is the standing instruction that a developer or operator gives a language model before the user's own input.

A TDM reservation is a rights holder's declaration that third parties may not use their content for text and data mining (TDM).

Technical SEO is the part of search engine optimization that makes sure search engines can fetch, render and index a website.

Text-to-HTML ratio (also code-to-text ratio) is the share of a page's HTML that is visible text.

TF-IDF (term frequency–inverse document frequency) is a weighting method from information retrieval.

Thin affiliate pages carry affiliate links but offer little original content, for example product descriptions copied unchanged from the …

Thin content describes pages that give visitors little or no added value.

Third-party scripts are JavaScript files that a website loads from domains it does not control.

Time to First Byte (TTFB) is the time between the start of navigation to a page and the moment the first byte of the response arrives. …

A title link is the clickable title of a result in Google Search.

A title rewrite happens when Google shows a different title in search results than the one in a page's <title> element.

A title tag is the HTML <title> element inside a page's <head>.

A token in the context of language models is the unit of text a model reads and writes.

A tokenizer is the component that splits text into tokens and assigns each token a numeric ID from a fixed vocabulary.

Tool calling, also called function calling or tool use, is the ability of a language model to answer with a structured request to run a …

The top heavy update, officially the page layout algorithm change, is a Google change announced on January 19, 2012.

Topical authority is an SEO idea that a website becomes a trusted source on a subject when it covers that subject broadly and in depth.

Topical map has a geographic meaning (a map showing terrain), but in SEO it is a plan: an overview of the topics, subtopics and pages a …

A topic cluster is a group of pages on one website that together cover a main subject.

Topic modeling is a text-mining technique that finds the main themes in a large set of documents without labeled training data.

A top-level domain (TLD) is the last label of a domain name, the part after the final dot, for example com in example.com.

Top stories is a section in Google Search that can appear when Google detects a news-oriented query.

Total Blocking Time (TBT) is a lab metric.

Toxic backlinks is a term from SEO tools for incoming links judged harmful to a site, for example links from spam sites or link networks.

In SEO and web analytics, tracking means recording what visitors do on a website, usually by code that runs in the browser and sends data …

A traffic drop is a marked decline in visits to a website.

Traffic sources describe where the visits to a website come from, for example search engines, other websites, social networks or direct …

A trailing slash is the forward slash at the end of a URL, as in https://example.com/foo/.

A training crawler is an AI crawler that fetches web pages to collect content for training AI models.

Training data is the collection of examples a machine learning model learns from.

Transactional intent describes a search in which the person wants to complete an action, most often a purchase, a booking, or a sign-up.

A transformer is a neural network architecture that processes text and other sequences with an attention mechanism, called self-attention.

Trust Flow and Citation Flow are two metrics from the SEO tool vendor Majestic.

TrustRank is a link-based method to separate reputable pages from web spam.

Twitter cards, now called X cards, are meta tags in a page's <head> that control how a shared link looks as a preview on X, with title …

unavailable_after is a robots rule that gives Google a date and time after which a page should no longer appear in search results.

Unique content is content that exists in this form on only one page and gives readers something of their own.

The Universal Commerce Protocol (UCP) is an open standard that lets AI agents discover products and complete purchases at businesses.

Universal search is Google's approach of blending results from several of its search services, such as images, video, news and maps, into …

Uptime monitoring is the recurring check of whether a website or service responds.

A URL (Uniform Resource Locator) is the address of a unique resource on the web, such as an HTML page, an image or a document.

URL case sensitivity describes whether uppercase and lowercase letters in a URL count as different.

URL discovery is the step in which a search engine learns that a URL exists, before it fetches the page.

URL hijacking is another name for typosquatting: registering domains that differ from a well-known brand's address only by a typing …

The URL Inspection tool is a feature of Google Search Console that shows how Google has indexed a single URL and how Google can fetch and …

URL mapping, in SEO, is the assignment of old URLs to new target URLs when the structure or domain of a website changes.

URL parameters are key and value pairs added to a URL after a question mark.

URL structure is the way a website builds its addresses: protocol, host, path, and optional parameters.

Usability is how easy and effective an interface is to use.

The user agent is the software that makes a request to a web server on behalf of a user, and the name of its HTTP request header.

User experience (UX) covers all aspects of a person's interaction with a company, its services and its products.

User-generated content (UGC) is content that users create instead of the site owner, such as reviews, forum posts, comments, photos and …

User-generated spam is spammy content that users add to a website through a channel meant for user content, such as comments, forum …

A user journey is the sequence of steps a person takes to reach a goal, such as choosing and buying a product.

User signals are measurable behavior data from searchers, such as click-through rate in search results, returning to the results page …

A user-triggered fetcher is an automated program that loads a web page because a person asked a product to do so.

UTM parameters are tags added to the end of a URL, such as utm_source and utm_medium, that tell an analytics tool which campaign, channel …

A vanity URL is a short, memorable web address that leads to a longer or more technical destination URL.

The Vary header is an HTTP response header that lists which request headers influenced the response, so that caches store and serve each …

A vector database stores embeddings, the number vectors that represent the meaning of text, images or audio, and retrieves the entries …

Vector search finds similar items by representing text, images or audio as vectors, called embeddings, and comparing the distance between …

Video schema is VideoObject structured data that describes a video on a web page.

Video SEO covers the steps that help videos get found, indexed and displayed in search engines: in regular Google Search, in Google Videos …

A video sitemap is an XML sitemap with extra details about videos embedded on pages of a site.

The viewport meta tag (<meta name="viewport">) gives browsers hints about how to size and scale the visible area of a page, mainly on …

Voice search is a search where the query is spoken instead of typed.

The WCAG (Web Content Accessibility Guidelines) are the W3C's technical standard for accessible web content.

Web accessibility means that websites, tools and technologies are designed so that people with disabilities can use them.

Web analytics is the measurement, collection, analysis and reporting of website data to understand and improve how a site is used.

A web application firewall (WAF) inspects the HTTP and HTTPS traffic that reaches a website or web application and blocks suspicious …

Web Bot Auth is a method for automated clients such as crawlers and AI agents to identify themselves to websites with a cryptographic …

Web components are a set of browser standards for creating reusable custom HTML elements with their own behavior and styling.

A web crawler (also called a crawler, spider, or bot) is a program that automatically fetches web pages and follows the links on them to …

A web directory is an online catalog of websites organized into categories and subcategories.

Web font loading describes how a page fetches custom font files and what the browser shows while they download.

A webhook is an HTTP request that one system sends automatically to a URL of another system when an event occurs.

Web hosting is the infrastructure that serves a website.

A webmaster is a person responsible for maintaining one or more websites.

WebMCP is a proposed web standard that lets a website expose structured tools to AI agents working in the browser.

WebP is an image format developed by Google for the web.

In web development, web performance is how quickly a website loads, becomes usable and reacts to input.

The Web Rendering Service (WRS) is the component of Google Search that renders pages and executes their JavaScript.

A web scraper is a program that automatically extracts data from web pages and converts it into a structured format such as a spreadsheet …

In SEO, a website migration is any major change in which a website's domain, URL structure, protocol, platform, or hosting changes.

A website migration checklist is an ordered list of checks for a site move, such as a domain change, a new platform or new URLs, so that …

Website monitoring is the automated, repeated testing of a website to confirm that it is available, loads quickly and works as expected.

Website navigation is the set of elements that lead visitors and crawlers from page to page.

A website relaunch is the overhaul of an existing website in which several layers change at once, for example design, structure, content …

Web spam (also search spam or SEO spam) describes practices that manipulate search results or mislead users instead of helping them.

White hat SEO is search engine optimization that stays within the guidelines of search engines.

WHOIS is a protocol and service for looking up registration data about domains and IP addresses, such as the registrar, name servers and …

www vs. non-www is the choice between www.example.com and example.com as the main address of a website.

x-default is a reserved value of the hreflang attribute.

XML (Extensible Markup Language) is a text-based format that describes data in nested elements with self-defined tags.

An XML sitemap is a file in XML format that lists the URLs of a website a search engine should crawl and index, optionally with the date …

The X-Robots-Tag is an HTTP response header that passes indexing and serving rules for a URL to search engines.

YMYL (Your Money or Your Life) describes topics where inaccurate or misleading content could harm people.

YouBot is the web crawler of the You.com search engine.

YouTube SEO is the optimization of videos and channels so they appear and get clicked more often in YouTube search and recommendations.

A zero-click search is a search that ends without a click on any result.