The SEO glossary.Plain-English definitions, no fluff.

Text in an image's `alt` attribute that describes the image. Used by screen readers and by search engines that cannot see the picture.

Accelerated Mobile Pages — an open-source HTML framework, originally backed by Google, for building fast-loading web pages.

The visible, clickable text inside a hyperlink. Search engines use it as a hint about the topic of the page being linked to.

A Search Console metric showing the average ranking of a site's topmost result for a query across all impressions, where 1 is the highest position.

A hyperlink on one website that points at another. Search engines treat backlinks as one signal of how the wider web vouches for a page.

A navigation trail showing where a page sits in a site's hierarchy. Google may display them in search results via BreadcrumbList structured data.

An HTML element that tells search engines which URL is the master copy when the same or similar content exists at multiple addresses.

A public dataset of real-world performance metrics collected from Chrome users, used to measure how sites are experienced in the field.

A mention of a business's name, address or phone number on another website, which Google can use as a signal when understanding a local business.

The percentage of search impressions that resulted in a click. CTR = clicks ÷ impressions × 100.

Showing search engines and users different content with the intent to manipulate rankings and mislead visitors.

A network of geographically distributed servers that cache and deliver web content from a location close to each user.

How recently a page was published or meaningfully updated, as signalled by visible dates, structured data, and substantive changes to the content itself.

A broad, significant change to Google's search ranking systems, rolled out several times a year and announced publicly.

A set of three Google metrics that measure real-world page experience: loading speed, interactivity and visual stability.

The number of URLs a search engine crawler will fetch and the rate at which it fetches them on a given site.

A condition that prevents Googlebot from successfully fetching or processing a URL, such as a server failure, DNS issue or HTTP error response.

The process by which search engines discover and download pages from the web using automated programs called crawlers.

A Core Web Vitals metric measuring how much visible content unexpectedly shifts position during the lifetime of a page.

A Search Console tool that asks Google to ignore specific inbound links when assessing a site, intended for cases where unnatural links may cause harm.

A regular HTML link with no rel qualification, which search engines crawl and treat as a standard endorsement of the destination page.

A page created mainly to rank for specific queries and funnel visitors to another destination rather than serve them directly.

Substantively identical or very similar content that appears at more than one URL, either within a single site or across different sites.

Title tags that are identical or near-identical across multiple pages on the same site, making the pages hard to tell apart in search results.

Serving a pre-rendered HTML version of a page to crawlers while delivering a client-rendered version to human visitors of the same URL.

Google's framework for assessing content quality across four lenses: Experience, Expertise, Authoritativeness and Trust.

Buying expired domains and repurposing them with low-value content mainly to exploit their prior ranking signals.

An HTML link that points from one website to a different domain, also called an outbound link from the source site's perspective.

A Search result that showed marked-up questions and answers from a page, now restricted and being deprecated by Google.

A small square icon that represents a site in browser tabs, bookmarks, and — when Google chooses to show it — alongside the site's results in mobile search.

A search result that surfaces an answer extracted from a single web page in a highlighted box at or near the top of Google's results page.

A web performance metric measuring the time from page load start to the first visible text, image, or non-blank canvas being rendered.

A retired Core Web Vital that measured the delay between a user's first interaction and the browser starting to process it.

A free Google listing that represents a real-world business across Google Search and Maps with details such as name, address, hours, photos and reviews.

A Google feed that surfaces content related to a user's interests based on their Web and App Activity, without an explicit search query.

A free Google service that lets site owners monitor, maintain, and troubleshoot how their site appears in Google Search results.

The generic name for Google's web crawlers — the automated software that discovers and fetches pages for inclusion in Google Search.

An HTML element (`<h1>`) used to mark the primary heading of a page, typically the most prominent visible title.

The hierarchy of `<h1>`–`<h6>` elements on a page, used to convey the order and nesting of sections to readers and assistive technologies.

Google's term for content created primarily to benefit people, demonstrating originality, expertise, and a clear understanding of the intended audience.

Text or links placed on a page so search engines can read them but human visitors cannot, used to manipulate rankings.

An HTML attribute or sitemap tag that tells search engines which language and region a page is intended for, so the right version is shown to the right user.

A three-digit response code returned by a server that tells the client — including search engine crawlers — the outcome of an HTTP request.

Hypertext Transfer Protocol Secure — the encrypted version of HTTP. Google uses HTTPS as a lightweight ranking signal.

The practice of structuring images and surrounding markup so search engines can discover, understand and surface them in image and web search results.

In Google Search Console, the number of times a link to a site appeared in Google Search results for a user, regardless of whether the user clicked it.

The process by which a search engine analyses a fetched page and stores information about it so the page can later be returned in search results.

A Core Web Vitals metric measuring how long a page takes to visually respond to a user interaction, sampled across the page's lifetime.

The practice of linking from one page on a site to another page on the same site. Helps users navigate and gives search engines more crawl paths.

A pop-up or overlay that obscures a page's main content and makes it harder for visitors to access what they came for.

The practice of making JavaScript-powered websites crawlable, renderable and indexable by search engines.

A JSON-based syntax for embedding structured data in a script tag, used to describe a page's content to search engines and other parsers.

An SEO community term for when multiple pages on the same site compete for the same query, splitting ranking signals between them.

The process of identifying the search terms people use to find information, products, or services related to a given topic.

Filling a page with keywords or numbers in an attempt to manipulate Google Search rankings.

An information box in Google's search results, automatically generated for an entity from sources like the Knowledge Graph and the open web.

A Core Web Vitals metric measuring how long the largest visible content element on a page takes to render after loading begins.

A technique that defers loading of off-screen images, iframes, or other resources until the user is about to scroll them into view.

An open-source automated tool from Google that audits a web page for performance, accessibility, SEO and other best practices.

The practice of acquiring inbound links from other websites, ranging from editorial outreach to schemes that Google classifies as link spam.

An SEO-community term for the ranking value that one page can pass to another through a link, related to what Google originally called PageRank.

Links created primarily to manipulate search rankings, which Google's spam policies treat as a violation that can affect a site's visibility.

A group of local business listings displayed with a map on Google Search, ranked by Google's local algorithm using relevance, distance and prominence.

The practice of optimising a business's online presence to surface in location-based search results, including the Local Pack and Google Maps.

A longer, more specific search query that typically has lower individual search volume but a clearer intent than broad terms.

A penalty applied by a Google reviewer when a site is found to violate the search spam policies, demoting or removing affected pages from results.

A short HTML attribute summarising a page, often used by search engines as the snippet shown beneath a result's title.

An HTML meta tag in a page's head that gives search engines page-level instructions on indexing and link following, such as noindex and nofollow.

The process of removing unnecessary characters from code such as comments and whitespace to reduce file size without changing behaviour.

A page loaded over HTTPS that also loads sub-resources — images, scripts, stylesheets — over insecure HTTP, weakening the security of the original page.

Google's practice of using the mobile version of a site as the primary basis for indexing and ranking.

A property of a web page that renders legibly and usably on phones without horizontal scrolling, tiny text, or close-packed tap targets.

A link given editorially by another site without solicitation, exchange or payment, contrasted with link schemes Google treats as spam.

A link attribute (`rel="nofollow"`) telling search engines not to associate the source page with — or pass ranking credit to — the linked page.

A robots directive that tells search engines not to include a page in their index, even if the URL is publicly reachable.

A protocol of meta tags (og:title, og:image, og:description, og:url) that lets a web page describe how it should appear when shared on social platforms.

Search results that aren't paid for by an advertiser, ranked by the search engine's algorithm based on relevance to the query.

Markup using schema.org's Organization type that describes a business so Google can understand and disambiguate it.

A page on a website that no other page on the same site links to, leaving crawlers without an internal path to discover it.

Google's umbrella term for signals describing how users perceive a page — Core Web Vitals, HTTPS, mobile usability, and absence of intrusive interstitials.

A Google Search Console report showing which of a site's URLs Google has indexed and the reasons others have not been.

How quickly a web page loads and becomes interactive, measured by metrics such as Largest Contentful Paint, Interaction to Next Paint, and Time to First Byte.

A Google tool that reports a web page's performance on mobile and desktop using both real-user field data and simulated lab data.

Splitting a long sequence of content (search results, products, articles) across multiple URL-distinct pages, navigated via numbered or next/previous links.

A link created in exchange for money, goods or services, which Google requires to be qualified with rel="sponsored" or rel="nofollow".

A SERP feature that displays a cluster of related questions, each expanding to show a featured-snippet-style answer drawn from a web page.

Markup based on schema.org's Product type that describes product details so Google can show richer results.

One of the many factors a search engine weighs when ordering results for a query, such as relevance, content quality, or usability.

A sequence of two or more redirects between an original URL and the final destination. Each hop adds latency and risk of signal loss.

Resources — typically CSS and synchronous JavaScript — the browser must fetch and parse before it can paint the first frame of a page.

Markup that tells the browser about connections or resources a page will need, so it can prepare them ahead of time.

A design approach that uses flexible layouts, media queries, and a viewport meta tag so a single HTML page adapts to any screen size.

A search result enhancement that shows a star rating or short review excerpt, generated from Review or AggregateRating structured data.

Search results enhanced with visual or interactive elements — review stars, prices, FAQs, recipe images — generated from a page's structured data.

A plain-text file at the root of a domain that tells crawlers which paths they may or may not request.

Producing many pages at scale primarily to manipulate search rankings rather than to help users.

Structured data added to a page that describes its content to search engines in a machine-readable format.

Content taken from other websites by automated means and republished, often with little or no original value added.

The underlying goal a person has when entering a query into a search engine — what they actually want to find, do, or know.

A URL that is readable, descriptive, and structured so that search engines and people can understand what a page is about from the address alone.

The page a search engine returns in response to a query, including the list of results and any features such as ads, knowledge panels and rich snippets.

A rendering strategy in which the server generates a page's full HTML on each request, rather than leaving the browser to build it with client-side JavaScript.

A substantial change to a website's URLs, hosting, structure or platform that requires search engines to discover and re-index the new setup.

The name Google displays above a page's title link in search results to identify which site the page belongs to.

Publishing third-party pages on an established site mainly to exploit that site's ranking signals, with little host oversight.

Additional links to a site's pages that Google may show beneath a main search result, deep-linking into pages it considers most useful.

A file, usually XML, that lists URLs on a site so search engines can discover and crawl them more efficiently.

A redirect that sends users to content different from what they or search engines were led to expect, to deceive.

A URL that returns an HTTP 200 status but displays content telling the user the page doesn't exist. Google treats it as a 404.

Google's published rules describing behaviours and techniques that can lower a site's ranking or remove it from search results.

A link marked with rel="sponsored" to indicate it was created as part of an advertisement, sponsorship, or other paid placement.

A digital certificate that binds a domain to a public key and lets browsers establish an encrypted HTTPS connection with the server.

Pages with little or no original value to users — for example, auto-generated text, scraped content, or copied affiliate descriptions.

A performance metric measuring the time between a request for a page and the first byte of the response arriving back at the browser.

The HTML `<title>` element on a page. Google often uses its content to generate the clickable headline (the "title link") in search results.

A lab metric that sums how long the browser's main thread was blocked by long tasks after First Contentful Paint.

A link marked with rel="ugc" to indicate it was created in user-generated content such as a forum post, comment, or review.

A Google Search Console feature that reports Google's indexed version of a specific page and tests whether a URL can be indexed.

Key-value pairs appended to a URL after a question mark, used to filter, sort, track or otherwise vary the response without changing the path.

The practice of marking up and hosting videos so Google can index them and surface them in video results, key moments, live badges and other features.

An HTML meta element that tells mobile browsers how to size the visible area of a page, typically with content="width=device-width, initial-scale=1".

An image format developed by Google that provides lossless and lossy compression, typically producing smaller files than PNG or JPEG.

A permanent redirect — an HTTP 301 status code telling clients and search engines that a URL has moved permanently to a new location.

A temporary HTTP redirect (status 302 Found). Search engines keep the original URL indexed because the move is signalled as temporary.

An HTTP 404 "Not Found" response, indicating the requested URL does not exist on the server. Google drops 404 URLs from its index over time.