167 terms
SEO GlossarySEO Terms A–Z
The core concepts of search engine optimization: how a page is crawled, indexed and represented in search results. From technical foundations and on-page signals to links and performance metrics, these are the terms you meet most often in SEO work. Every entry opens with a short, quotable definition, then explains how the concept works, why it matters and where people commonly go wrong. Definitions are kept consistent with primary documentation such as Google Search Central; undocumented ranking factors are not presented as facts.
Searches term names and alternate names; on category pages also the short definitions.
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- AI Mode (Google)AI Mode is a conversational AI search experience offered as a separate tab in Google Search. It breaks complex, multi-part questions into subtopics, runs searches for them simultaneously and combines the findings into one response with links to supporting websites, and it lets users ask follow-up questions. It started as a Labs experiment in March 2025 and opened to everyone in the US in May 2025.Professional · SEO · GEO
- AI OverviewsAI Overviews is a Google Search feature that shows an AI-generated summary, together with links to supporting web pages, above the regular results for some queries. It began in 2023 as the Search Labs experiment SGE (Search Generative Experience) and rolled out to all users in the United States in May 2024. It appears only when Google's systems judge that it adds value beyond classic results.Core · SEO · GEO
- Alt TextAlt text is the short text placed in an HTML image's alt attribute that stands in for the image when someone cannot see it. It is written first for screen reader users and for cases where the image fails to load; search engines also use it to understand what an image shows. Purely decorative images get an empty alt attribute (alt="") so assistive technology skips them.Core · SEO · Web Design
- Anchor TextAnchor text is the visible, clickable text of a hyperlink, the content between an a element's opening and closing tags. It tells users and search engines where the link leads and what the target page is about. For image links, the image's alt attribute plays this role. Good anchor text is short, descriptive and fits naturally into the surrounding sentence.Core · SEO
- Anchor Text ProfileAn anchor text profile is the distribution, by type, of the link text used in all the backlinks pointing to a site or page: brand names, naked URLs, generic phrases, and partial-match and exact-match keywords. Links that are earned naturally produce a varied profile, usually dominated by brand and URL anchors. An unusual concentration of exact-match keyword anchors is one of the typical traces of manipulative link building.Advanced · SEO
- Article SchemaArticle schema is structured data that describes a news story, blog post or article page using schema.org's Article, NewsArticle or BlogPosting types. It states the headline, authors, publication and modification dates and images explicitly. Google says it helps show better title text, images and date information for the article in search results. It has no required properties.Professional · SEO · GEO
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- BacklinkA backlink is a link from a page on another website to a page on your site. From the linking site's point of view, the same link is an outbound link. Search engines use backlinks to discover pages and to understand how widely other sites reference a piece of content. What matters is not the raw count but whether links are relevant and earned naturally.Core · SEO
- Bing Webmaster ToolsBing Webmaster Tools is Microsoft's free toolset that shows site owners how Bing crawls, indexes and ranks their site. Besides search performance, URL inspection, sitemaps, IndexNow submission, backlink and keyword data, it includes AI Performance, which reports how often the site is cited as a source in Microsoft Copilot and AI-generated answers in Bing.Professional · SEO · GEO
- BingbotBingbot is Microsoft's main web crawler for the Bing search engine. It identifies itself with a user-agent containing bingbot/2.0, renders pages with an engine based on the latest stable Microsoft Edge, and obeys the bingbot token in robots.txt. Because Microsoft Copilot uses the Bing search service when it needs web information, content Bingbot crawls can also become a source for those answers.Professional · SEO · GEO
- Black Hat SEOBlack hat SEO is the umbrella term for tactics that try to manipulate search rankings by breaking search engine rules, such as buying links, cloaking, doorway pages, keyword stuffing or mass-produced low-value content. Its opposite, white hat SEO, works within search engine guidelines and focuses on creating value for users. Both are industry jargon; in Google's own documentation, the boundary is drawn by its spam policies.Core · SEO
- Brand MentionA brand mention is any reference to a brand, product or organisation by name on a source other than its own website, such as a news article, blog, forum, social post, video or podcast. It may or may not include a link; one without a link is called an unlinked mention. Mentions show how and in what context a brand is discussed, and they are one of the sources from which AI systems learn about it.Professional · SEO · GEO
- BreadcrumbA breadcrumb is a secondary navigation element that shows where the current page sits in a site's hierarchy as a chain of links, such as Home › Category › Page. The same trail can be marked up as structured data with schema.org's BreadcrumbList type, which Google can use on desktop search results to show the page's position as a readable path.Core · SEO · Web Design
- Broken LinkA broken link is a hyperlink that no longer takes the user to a working page: the target returns 404 or 410, the domain no longer resolves, or the server responds with an error. Broken links occur both in internal links between a site's own pages and in external links to other sites. They strand visitors, waste crawler time and signal that content is not being maintained.Core · SEO
- Broken Link BuildingBroken link building is a link-earning technique in which you find links on other sites that point to resources that no longer work, tell the site owner about them and suggest your own equivalent content as a replacement. Its value comes from solving a real problem for the publisher; whether to change the link is entirely their decision, and no payment or link swap is offered in return.Professional · SEO
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- Canonical URLA canonical URL is the address a site marks as the preferred version of a page when the same or very similar content is reachable at several URLs. It is usually declared with a rel=canonical link element in the page head, an HTTP Link header, a permanent redirect or sitemap inclusion. Google treats the declaration as a strong signal, not a binding directive.Core · SEO
- CanonicalizationCanonicalization is the process by which a search engine groups URLs with the same or very similar content and selects one of them as the representative, or canonical, version. Google weighs signals such as redirects, rel=canonical annotations, sitemap inclusion, HTTPS and hreflang to make that choice; the site owner's preference is a strong signal, but the final decision belongs to the search engine.Professional · SEO
- Click-Through Rate (CTR)Click-through rate (CTR) is the number of clicks a link receives divided by the number of times it was shown. In SEO it usually means organic CTR as reported in Google Search Console: how often a site was clicked relative to how often it appeared in search results. Ranking position, the title link, the snippet, rich results and other SERP features all strongly influence it.Core · SEO · Performance & Analytics
- CloakingCloaking is the practice of deliberately presenting different content to search engine crawlers and to human visitors in order to manipulate rankings and mislead users. It is usually done by a server that checks the requester's user agent or IP address and returns one page to Googlebot and another to people. Cloaking is explicitly prohibited by Google's spam policies.Professional · SEO
- CLS (Cumulative Layout Shift)CLS (Cumulative Layout Shift) is a unitless score that measures how much visible content moves unexpectedly on a page, without the user causing it. It is the visual-stability metric of the Core Web Vitals. At the 75th percentile of visits, a CLS of 0.1 or less is considered good and anything above 0.25 poor.Professional · SEO · Web Design · Performance & Analytics
- Content DecayContent decay is the slow, sustained loss of organic clicks and visibility by a page that once performed well. Unlike a sudden technical failure, it unfolds over months, usually because the information has aged, competitors have published better pages, search intent or the results page layout has changed, or demand for the topic has fallen.Professional · SEO
- Content FreshnessContent freshness is how recent the information on a page is and how clearly that recency is communicated to readers and machines. Google's 'query deserves freshness' systems surface newer content for queries where up-to-date information is expected; for queries where it is not, being new is no advantage by itself. In AI-generated answers the same idea appears as source freshness.Professional · SEO · GEO
- Content GapA content gap is a topic, question or search intent that your audience is looking for and that clearly belongs to your subject area, but that your site does not cover or covers only partially. Gaps are usually found by comparing the queries competitors rank for, the questions customers repeatedly ask and the subtopics missing from existing pages against what your site actually offers.Professional · SEO
- Core UpdateA core update is a significant, broad change Google makes to its search algorithms and systems several times a year. It does not target specific sites or pages; it recalibrates how content is assessed overall. Major core updates are announced on the Google Search Status Dashboard, and their rollout typically takes from several days to a few weeks.Professional · SEO
- Core Web VitalsCore Web Vitals are a set of three metrics Google defines to measure real-world user experience on a web page: Largest Contentful Paint (LCP) for loading, Interaction to Next Paint (INP) for responsiveness and Cumulative Layout Shift (CLS) for visual stability. A page meets the 'good' thresholds when, at the 75th percentile of visits, LCP is 2.5 seconds or less, INP is 200 milliseconds or less and CLS is 0.1 or less.Core · SEO · Web Design · Performance & Analytics
- Crawl BudgetCrawl budget is the set of URLs on a site that Google can and wants to crawl within a given period. It is shaped by the crawl capacity limit, which reflects how much load the server can handle, and crawl demand, which reflects how much Google wants to crawl the pages. Google says it mainly matters for very large or rapidly changing sites, not for most websites.Advanced · SEO
- Crawl DepthCrawl depth is the minimum number of clicks needed to reach a page from a site's starting point, usually the homepage, by following internal links. The homepage sits at depth 0 and pages it links to directly sit at depth 1. Deeper pages tend to be discovered and recrawled more slowly, which is why important pages are best kept within a shallow structure.Professional · SEO
- CrawlabilityCrawlability is the property of a website that determines how easily search engine crawlers can reach its pages, download them and follow the links they contain. It depends on the site's link structure, its robots.txt rules, the status codes and response times its server returns, how security layers treat bots, and whether navigation works without relying on JavaScript events.Core · SEO
- CrawlingCrawling is the process by which search engines and other automated systems use programs called crawlers (also bots or spiders) to discover web pages and download their content. Google's crawler, Googlebot, finds new URLs by following links on pages it already knows and by reading submitted sitemaps; crawled pages are then processed for possible indexing.Core · SEO
- CrUX (Chrome UX Report)CrUX (Chrome User Experience Report) is Google's public dataset of real-user performance measurements collected anonymously from eligible Chrome users. It reports metrics, above all the Core Web Vitals, at page (URL) and site (origin) level over 28-day windows. PageSpeed Insights and Search Console are built on it, and the data can be queried directly through the CrUX API, the History API and BigQuery.Professional · SEO · Performance & Analytics
- CSR (Client-Side Rendering)CSR (client-side rendering) is a rendering approach in which page content is built by JavaScript in the user's browser rather than on the server. The server typically sends a near-empty HTML shell plus JavaScript bundles; the browser runs that code, fetches data from APIs and writes the interface into the DOM. It enables fluid, app-like transitions but makes first paint, and what search engines can see, depend on JavaScript.Professional · SEO · Web Design · Software
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- DefinedTerm and DefinedTermSetDefinedTerm and DefinedTermSet are schema.org types: DefinedTerm represents a word, abbreviation or phrase with a formal definition, while DefinedTermSet represents the glossary, classification scheme or code list those terms belong to. A term links to its set through inDefinedTermSet, and the set lists its terms through hasDefinedTerm. Google has no rich result for these types; their purpose is to name concepts and definitions explicitly for machines.Advanced · SEO · GEO
- DeindexingDeindexing is the removal of a previously indexed page or site from a search engine's index, so that it no longer appears in search results. It can be deliberate, done by the site owner with noindex, a 404 or 410 response or access control, or unintended, caused by misconfiguration, quality assessments, a hacked site or a manual action.Professional · SEO
- DisavowTo disavow links is to ask Google, through a tool in Google Search Console, not to take certain backlinks or whole domains into account when assessing your site. Google says the tool should only be used when a site has a considerable number of spammy, artificial or low-quality links that have caused, or are likely to cause, a manual action, and that most sites never need it.Advanced · SEO
- Domain AuthorityDomain Authority (DA) is a third-party score from the SEO software company Moz that predicts, on a scale of 1 to 100, how likely a domain is to rank in search results. It is based largely on backlink data. It is not a Google metric, and Google has stated that it does not use a domain authority score like this in ranking.Professional · SEO
- Domain NameA domain name is a unique, human-readable name registered in the DNS hierarchy that lets people reach a website or service without knowing its IP address. In example.co.uk, “uk” is the country-code top-level domain and “example” is the registered name. Domains are not bought outright: they are registered through a registrar for a fixed period and must be renewed before they expire.Core · SEO · Security & Infrastructure
- Domain Rating (DR)Domain Rating (DR) is a third-party metric from the SEO software company Ahrefs that expresses the strength of a domain's backlink profile on a 0–100 scale, relative to the other sites in Ahrefs' database. Its page-level counterpart is URL Rating (UR). DR is not a Google signal: Google does not use it, and the score is a relative estimate built solely from Ahrefs' own crawl and link data.Professional · SEO
- Duplicate ContentDuplicate content is identical or substantially similar content that is accessible at more than one URL. It usually arises from technical causes such as URL parameters, www and HTTPS variants, or sorting and filter pages. Google picks one version as canonical; duplicate content within a site is not in itself a penalty or a reason for a manual action.Core · SEO
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- E-commerce SEOE-commerce SEO is the work that helps an online store's category and product pages appear in search results and on Google's shopping surfaces. Its main concerns are managing filter and variant URLs, product structured data and product feeds, handling out-of-stock and discontinued items, avoiding duplicated manufacturer descriptions and giving category pages genuinely useful content.Professional · SEO · CMS & E-commerce
- E-E-A-TE-E-A-T stands for Experience, Expertise, Authoritativeness and Trust, the concepts Google's Search Quality Rater Guidelines use to assess page quality. Trust sits at the centre and is the most important of the four. According to Google, E-E-A-T itself is not a specific ranking factor; its automated systems use a mix of signals to identify content that demonstrates these qualities.Core · SEO · GEO
- EntityAn entity is something that search engines and AI systems recognize as a single, distinguishable thing: a person, company, product, place or concept. Entities are identified by their identity and attributes rather than by the words used to name them. Consistent naming, structured data and sameAs links help systems merge different spellings into one entity and keep similarly named entities apart.Core · SEO · GEO · AI Visibility
- Evergreen ContentEvergreen content is content whose subject and answer do not go out of date, so it keeps being searched for and read months or years after publication. How-to guides, explanations of fundamental concepts and answers to perennial questions are typical examples. Unlike news and trend pieces, its traffic does not collapse after an early peak, but it still needs maintenance.Core · SEO
- External LinkAn external link is a hyperlink from a page on one site to a page on a different domain. For the linking site it is an outbound link; for the site receiving it, the same link is a backlink. External links are used to cite sources, point readers to deeper information and make claims verifiable, while paid, user-generated or untrusted links are qualified with rel attribute values.Core · SEO
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- Faceted NavigationFaceted navigation is an interface that lets users narrow a list by several attributes at once, such as colour, size, brand and price, and is common on ecommerce category pages. Because each filter combination usually produces its own URL, it can, if left unmanaged, lead search engines to crawl an almost unlimited number of low-value addresses and discover new content more slowly.Advanced · SEO · CMS & E-commerce
- FAQ Schema (FAQPage)FAQ schema is structured data that marks up a page's frequently asked questions with schema.org's FAQPage, Question and Answer types; every question and answer must match text visible on the page. In 2023 Google limited FAQ rich results to well-known, authoritative government and health sites, and from 7 May 2026 it stopped showing this rich result type in Google Search altogether.Professional · SEO · GEO
- FaviconA favicon is the small icon that represents a website in browser tabs, bookmarks, history and next to the site name in Google search results. It is usually declared with a link rel="icon" element in the page head. To appear in Google, it must be square, at least 8×8 pixels, and both the icon file and the home page must be crawlable.Core · SEO · Web Design
- Featured SnippetA featured snippet is a search result format in which Google shows an excerpt from a page it judges to answer the query well, placing the text before the page title in a prominent box on the results page. Pages are selected automatically by Google's systems; no markup can request it. Site owners can only restrict it with nosnippet, max-snippet or data-nosnippet.Professional · SEO · GEO
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- Google Business ProfileGoogle Business Profile is a free profile through which a business manages the name, address, phone number, opening hours, categories, photos and reviews shown in Google Search and Google Maps. It was formerly called Google My Business. It is the main data source behind the map-based local pack in local searches and behind business listings in Maps, and a business must be verified before it can manage the information.Core · SEO
- Google Merchant CenterGoogle Merchant Center is a free console where businesses send Google their product data, store details, shipping and return settings. That data lets products appear in free listings across Google Search, the Shopping tab, Images and other Google surfaces, and, once a Google Ads account is linked, the same product data powers Shopping ads.Professional · SEO · CMS & E-commerce
- Google Search ConsoleGoogle Search Console is Google's free, official set of tools that shows site owners how their site performs in Google Search. It reports impressions and clicks per query and page, indexing status, crawl problems, Core Web Vitals, manual actions and security issues, and provides tools such as URL Inspection and sitemap submission.Core · SEO
- Google Spam PoliciesGoogle's spam policies are the rules content must not violate to be eligible to appear in Google web search results. They define practices that manipulate rankings or mislead users, including cloaking, doorway abuse, keyword stuffing, link spam, scaled content abuse, site reputation abuse and expired domain abuse. Sites that violate them may rank lower or not appear in results at all.Professional · SEO
- GooglebotGooglebot is the name of the main crawler Google Search uses to discover and download web pages. It comes in two types, Googlebot Smartphone, which simulates a mobile user, and Googlebot Desktop, which simulates a desktop user; both obey the same Googlebot token in robots.txt. Googlebot renders pages with a recent version of Chrome and identifies itself in the user-agent header.Core · SEO
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- Heading Structure (H1–H6)Heading structure is the way a web page's content is divided into sections with the HTML heading elements h1 through h6, and the logical hierarchy those headings form. The h1 usually states the page's main topic, while lower levels mark sections and subsections. A clear heading structure helps readers scan, lets screen reader users navigate and helps search engines understand how the content is organized.Core · SEO · Web Design
- Helpful ContentHelpful content is Google's term for content created primarily to benefit a specific audience rather than to attract search traffic. The idea began as a separate helpful content system in 2022 and became part of Google's core ranking systems in March 2024, so helpfulness is now assessed through a variety of signals rather than one dedicated classifier.Professional · SEO
- HreflangHreflang is an HTML attribute that tells search engines about the versions of a page written for other languages or regions. It is added with rel=alternate link elements, HTTP headers or an XML sitemap, and Google uses it to show each user the URL that best matches their language and location. Annotations must be reciprocal, and an x-default value can define a fallback.Professional · SEO
- HTTP HeaderAn HTTP header is a name-value line of metadata, written as “Name: value”, that comes before the body of an HTTP request or response. Request headers tell the server which host is wanted, what formats the client accepts and who is calling; response headers describe the content type, caching rules, cookies and security policies. Header names are case-insensitive, and the standard fields are defined in RFC 9110 and related specifications.Core · SEO · Software · Security & Infrastructure
- HTTP Status CodeAn HTTP status code is the three-digit number a server returns with every response to report the outcome of a request. The first digit gives the class: 2xx success, 3xx redirection, 4xx client error and 5xx server error. Search engines use these codes to decide whether to index a page, whether to follow a redirect and how fast to crawl a site.Core · SEO · Software
- HTTPSHTTPS (Hypertext Transfer Protocol Secure) is HTTP carried over a connection encrypted with TLS. It prevents third parties from reading or altering the data exchanged between browser and server, and the site's certificate lets the browser confirm it is talking to the genuine domain. Browsers now label plain HTTP pages as not secure, and Google prefers the HTTPS version of a page as canonical.Core · SEO · Security & Infrastructure
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- Image SEOImage SEO is the work that helps a site's images be found, understood and shown for relevant queries on Google Images, as text-result thumbnails, in Discover and in visual search. It covers serving images in crawlable HTML, descriptive alt text and file names, the context of the page an image sits on, image sitemaps and metadata that signals a page's preferred preview image.Professional · SEO · Web Design
- IndexabilityIndexability describes whether a page is eligible to be added to a search engine's index. An indexable page can be crawled, returns a 200 status code, carries no noindex rule, declares itself as canonical, produces readable content when rendered and offers distinct value. Meeting these conditions does not guarantee indexing; it removes the technical and content barriers in its way.Core · SEO
- IndexingIndexing is the step in which a search engine analyses a crawled page and stores it in its index, the database from which search results are drawn. During indexing Google processes the text, headings, images and structured data, and picks a canonical version among near-duplicate pages. Only pages that are in the index can appear in organic results.Core · SEO
- IndexNowIndexNow is an open protocol that lets a website notify participating search engines the moment a URL is added, updated or deleted. The site proves ownership with a key file and submits changed URLs in a simple HTTP request, and a notification sent to one engine is shared with the others. Microsoft Bing, Yandex, Naver, Seznam.cz and Yep support it; Google does not participate.Professional · SEO
- Information ArchitectureInformation architecture (IA) is the structural design of a website or app: how its content is grouped, what those groups and pages are called, and how people move between them. It covers organisation schemes, labelling, navigation and search. Good IA lets users find what they need without thinking about it, and the same structure, expressed through internal links and URLs, shapes how search engines understand the site.Professional · SEO · Web Design
- INP (Interaction to Next Paint)INP (Interaction to Next Paint) is the Core Web Vitals metric for responsiveness. It measures the delay between a user's clicks, taps or key presses and the next visual update on screen, and reports one of the slowest interactions observed during the page's lifetime. 200 milliseconds or less is good and more than 500 milliseconds poor. INP replaced First Input Delay (FID) in March 2024.Professional · SEO · Web Design · Performance & Analytics
- Internal LinkAn internal link is a hyperlink from one page of a website to another page on the same site. Navigation menus, links within body text, breadcrumbs and footer links all count. Internal links let visitors move through the site, help search engines discover pages, and, through their anchor text, signal how pages relate to each other by topic.Core · SEO
- International SEOInternational SEO is the technical and content work that makes a website show the right language or country version to the right audience in search. It covers choosing between country-code domains, subdomains and subdirectories, annotating language and regional versions with hreflang, signalling a target country (geotargeting) and localising content rather than merely translating it.Professional · SEO
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- JavaScript SEOJavaScript SEO is the part of technical SEO that makes sure websites whose content, links or meta data are generated by JavaScript can be crawled, rendered and indexed correctly by search engines. Its core topics are the rendering approach (server-side rendering, static generation or client-side rendering), link markup, routing and status codes, and how much critical signals depend on JavaScript.Advanced · SEO · Software
- JSON-LDJSON-LD (JSON for Linking Data) is a W3C standard for expressing linked data in JSON syntax. On websites it is mostly used inside a script element of type application/ld+json to add structured data based on the schema.org vocabulary. Keywords such as @context, @type, @id and @graph describe entities and the relationships between them without touching the page's visible HTML.Professional · SEO · GEO
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- KeywordA keyword is a word or phrase that represents the topic a page aims to be found for in search engines. It summarises the queries people type: one keyword stands for many different phrasings and variants that share the same intent. In SEO, content planning, on-page optimisation and performance tracking are all organised around keywords.Core · SEO
- Keyword CannibalizationKeyword cannibalization is when two or more pages on the same site target the same search intent and end up competing for the same queries. The search engine may struggle to settle on one URL, rankings can fluctuate between them and link signals get split. Pages that merely share a keyword are not cannibalizing each other; the problem arises when their intent overlaps.Professional · SEO
- Keyword DifficultyKeyword difficulty (KD) is a score, usually from 0 to 100, that third-party SEO tools calculate to estimate how hard it will be to reach the first page of organic results for a keyword. It is not a metric Google publishes or uses. Each tool applies its own formula, and most rely heavily on the link profiles of the pages currently ranking.Professional · SEO
- Keyword ResearchKeyword research is the process of finding out which phrases your audience uses in search engines, with what intent and how often, and turning that into decisions about pages and content. It covers collecting search queries, grouping them by intent, assessing them for volume and competition, and mapping each group to a single page on your site.Core · SEO
- Keyword StuffingKeyword stuffing is the practice of filling a web page with keywords or numbers in an unnatural way in an attempt to manipulate search rankings. Typical forms are repeating the same phrase out of context in body copy, headings or image alt text, and adding long blocks of city names or phone numbers. It violates Google's spam policies and makes pages harder to read.Core · SEO
- Knowledge GraphA knowledge graph is a data structure that stores entities such as people, organizations, places and concepts as nodes, and the relationships between them as edges. Search engines and AI systems use it to work out which entity a query refers to and to look up facts about it. Google's knowledge panels in search results are drawn from its Knowledge Graph.Professional · SEO · GEO
- Knowledge PanelA knowledge panel is the information box Google shows on the results page when someone searches for a person, organisation, place or thing that exists in its Knowledge Graph, giving a quick summary of facts about that entity. Panels are generated automatically from sources across the web, data partners and edits suggested by verified entities, and an official representative can claim a panel to suggest changes.Professional · SEO · GEO
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- LastmodLastmod is an optional element in an XML sitemap that states, in W3C Datetime format, when a URL's content last changed in a meaningful way. Google uses it as a signal when scheduling recrawls of URLs it has already discovered, but only if the values are consistently and verifiably accurate. Dates that do not reflect reality are eventually disregarded.Professional · SEO
- Lazy LoadingLazy loading is the technique of loading resources such as images, iframes or code only when they are actually needed, rather than all at once when the page opens; for images, that usually means when the user scrolls near them. The goal is to reduce how much data is downloaded on initial load. Browsers support it natively for images and iframes through the loading="lazy" attribute.Professional · SEO · Web Design · Performance & Analytics
- LCP (Largest Contentful Paint)LCP (Largest Contentful Paint) is the time from when a page starts loading until the largest image or text block visible in the viewport is rendered. It approximates when the user sees the page's main content and is one of the three Core Web Vitals. At the 75th percentile of visits, 2.5 seconds or less is considered good and more than 4 seconds poor.Professional · SEO · Web Design · Performance & Analytics
- LighthouseLighthouse is an open-source, automated auditing tool from Google that loads a web page in a controlled environment and scores it from 0 to 100 in categories such as performance, accessibility, best practices and SEO, along with concrete improvement suggestions. It runs in Chrome DevTools, behind PageSpeed Insights, from the command line and as a Node module in CI pipelines. Its results are lab data, not measurements from real users.Core · SEO · Performance & Analytics
- Link EquityLink equity is the SEO term for the ranking value a link is assumed to pass to the page it points to; "link juice" is its informal nickname. The idea goes back to PageRank, which treats links as votes passed between pages. Google uses neither term and does not disclose how it values links in detail, so link equity is best understood as a practical model for the fact that links carry signals.Professional · SEO
- Local SEOLocal SEO is the work of making a business with a physical location, or one that serves a defined area, more visible in location-based searches and map results. It covers a complete and accurate Google Business Profile, location pages on the website, consistent name, address and phone details, customer reviews and links or mentions from local sources.Core · SEO
- LocaleA locale is an identifier that defines the language and regional conventions software uses for a user. On the web it is usually expressed as a BCP 47 language tag such as en-US or tr-TR. The locale determines the interface language as well as how dates, times, numbers and currencies are formatted, how text is sorted and how upper- and lowercase conversions work.Professional · SEO · Web Design · Software
- Log File AnalysisLog file analysis is the practice of examining a web server's access logs to see how search engine bots and other crawlers actually crawl a site. It shows, request by request, which URLs are fetched and how often, which status codes bots receive and where crawl activity is spent. It is the most detailed source of crawl data, complementing the summarised reports in Search Console.Advanced · SEO
- Long-Tail KeywordA long-tail keyword is a specific search phrase that few people search for individually but that carries a very clear intent, and is usually longer than generic terms. On the search demand curve it belongs to the long tail of countless low-volume queries stretching behind the few heavily searched head or short-tail keywords; each tail query is small, but together they account for a large share of all searches.Core · SEO
- LSI KeywordsLSI keywords is a misleading SEO label for terms that are semantically related to a topic. LSI, latent semantic indexing, is an information retrieval technique developed in the late 1980s, and Google has said it does not use so-called LSI keywords. People who use the term usually mean the related concepts that naturally appear in text that covers a topic thoroughly.Professional · SEO
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- Manual ActionA manual action is a penalty Google applies when a human reviewer determines that pages on a site do not comply with Google's spam policies. Affected pages can be ranked lower or removed from search results entirely. Site owners are notified through the Manual Actions report and messages in Search Console, and can request a review once the problem has been fixed.Professional · SEO
- Meta DescriptionA meta description is the short summary of a page placed in a name=description meta tag in the HTML head. Search engines may use it as the snippet shown under a result, but they can also generate a snippet from the page text that better fits the query. Google has stated it does not use the meta description as a ranking factor; its effect is on how the result reads.Core · SEO
- Meta Robots TagThe meta robots tag is an HTML meta element placed in a page's head that tells search engines whether the page may be indexed, whether its links should be followed and how it may be presented in results. name="robots" addresses all crawlers, while values such as name="googlebot" address one; the content attribute holds comma-separated directives such as noindex, nofollow, nosnippet or max-snippet.Core · SEO
- Meta Title (Title Tag)A meta title is the text in a web page's title element, inside the HTML head. It appears in the browser tab, in bookmarks and usually as the clickable headline of a search result. Strictly speaking it is not a meta tag, but the industry calls it one. Google builds most result headlines from it, yet may use other on-page sources when they describe the page better.Core · SEO
- MicrodataMicrodata is a way of embedding structured data directly into HTML elements using attributes such as itemscope, itemtype and itemprop, defined as part of the HTML standard. The visible text of the page becomes machine-readable data at the same time. Google supports Microdata alongside JSON-LD and RDFa, but recommends JSON-LD because it is easier to maintain.Advanced · SEO
- Mixed ContentMixed content occurs when a page loaded over HTTPS requests some of its resources, such as images, scripts, stylesheets or iframes, over unencrypted HTTP. Those resources can be read or altered in transit. Modern browsers automatically upgrade image, audio and video requests to HTTPS and block other types such as scripts and stylesheets, which can leave the page looking broken.Professional · SEO · Security & Infrastructure
- Mobile-FirstMobile-first has two related meanings. As a design approach, it means designing and coding for the smallest screens first and then enhancing the layout for larger ones. In search, mobile-first indexing means Google crawls pages with its smartphone crawler and uses the mobile version of a site's content for indexing and ranking.Core · SEO · Web Design
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- NAP (Name, Address, Phone)NAP stands for Name, Address, Phone and refers to keeping these core business details identical across the website, Google Business Profile, directories and social profiles. A mention of a business's NAP details on another website is called a local citation. Consistent NAP data makes it easier for search engines and AI systems to recognize the business as one accurate record rather than several conflicting ones.Professional · SEO
- NofollowNofollow is a link annotation, rel=nofollow, that tells search engines a site does not vouch for a link and does not want to be associated with the target. It can also be set for a whole page in the robots meta tag. In 2019 Google added sponsored for paid links and ugc for user-generated links; all three values are now treated as hints rather than strict directives.Professional · SEO
- NoindexNoindex is a robots rule that asks search engines not to include a page or file in their index. It is applied with a robots meta tag in the page head or with an X-Robots-Tag HTTP response header. Google obeys it, but only after crawling the URL and seeing the rule, so a noindexed page must not be blocked in robots.txt.Core · SEO
- NosnippetNosnippet is a robots directive that asks search engines not to show a text snippet or video preview for a page in search results. It applies to the whole page through a meta tag or the X-Robots-Tag header, while the data-nosnippet attribute excludes specific parts of the text. According to Google, nosnippet also stops content from being used as direct input for AI Overviews and AI Mode.Professional · SEO · GEO
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- Off-Page SEOOff-page SEO covers the activities that influence a website's search visibility but happen outside the site's own pages. Links from other websites (backlinks), brand mentions, digital PR, business profiles and customer reviews all belong here. The goal is for the site to be recognised as a trustworthy source that others genuinely reference.Core · SEO
- On-Page SEOOn-page SEO is the optimization of an individual web page's own content and HTML so that both people and search engines can understand what it is about and judge its relevance. It covers content quality and fit with search intent, the title tag, meta description, heading hierarchy, internal links, image alt text and structured data.Core · SEO
- Open GraphOpen Graph is a meta tag protocol that defines the title, description, image and URL shown when a page is shared on social networks or in messaging apps. It was created by Facebook, and its tags go in the HTML head with the og: prefix. X (formerly Twitter) uses its own twitter: card tags but falls back to the Open Graph values when its title, description or image tags are missing.Core · SEO · Web Design
- Open RedirectAn open redirect is a vulnerability where a site redirects visitors to a destination taken from a URL parameter without validating it. Because the link starts with a trusted domain, users, email filters and search engines treat it as belonging to that site, while the visitor actually lands on a phishing or spam page. In login and OAuth flows, an open redirect can also help leak authorization codes or tokens.Advanced · SEO · Security & Infrastructure
- Organization SchemaOrganization schema is structured data that describes a company or institution with schema.org's Organization type: its name, website, logo, contact details, official identifiers and profiles on other platforms. Google can use it to understand the organisation and to decide which logo to show in search results and the knowledge panel. It has no required properties and usually lives on the home page or the about page.Professional · SEO · GEO
- Orphan PageAn orphan page is a page that receives no internal links from any other page on the same site, so it cannot be reached through menus, categories or in-content links. Visitors cannot find it by browsing, and search engines can only discover it through other routes such as the XML sitemap or external links, which makes its importance harder for them to judge.Professional · SEO
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- Page ExperiencePage experience is Google's term for how good an experience a page offers users beyond its information content. It covers Core Web Vitals, HTTPS, displaying well on mobile, and avoiding ads that swamp the main content and intrusive interstitials. Google says there is no single page experience signal; its ranking systems look at a variety of signals that align with these aspects.Professional · SEO · Performance & Analytics
- PageRankPageRank is the link analysis algorithm developed by Larry Page and Sergey Brin at Stanford that estimates a page's importance from the number and importance of the pages linking to it. It underpinned Google's ranking when the company launched. Google says the algorithm has evolved considerably since then and remains part of its core ranking systems, while the public 0–10 Toolbar PageRank score was retired years ago.Professional · SEO
- PageSpeed InsightsPageSpeed Insights (PSI) is Google's free web tool that reports the performance of a URL separately for mobile and desktop. The top of the report shows real-user data collected from Chrome users through the Chrome UX Report, including the Core Web Vitals assessment; the bottom shows a Lighthouse lab test with a performance score and specific diagnostics. The same data is available through an API.Core · SEO · Performance & Analytics
- PaginationPagination is the splitting of a long list, such as products, blog posts or search results, across several pages. Besides numbered pages it covers infinite scroll, which loads more items as the user scrolls, and "load more" buttons. For SEO the real question is whether items deep in the list can be discovered, which requires each page to have its own URL and real links.Professional · SEO · Web Design
- People Also AskPeople Also Ask (PAA) is a Google search results feature that shows questions related to the original query as an expandable list; Google calls it a related questions group. Expanding a question reveals a featured snippet taken from a web page, with a link to the source. The questions are generated automatically, and site owners cannot control which ones appear.Professional · SEO · GEO
- PermalinkA permalink is the full URL of a post, page or archive in a content management system, intended to stay unchanged for the long term. In systems such as WordPress the permalink format is set by a site-wide setting, and if that structure is changed after publication, every old address has to be connected to its new one with a permanent redirect.Core · SEO · CMS & E-commerce
- Product FeedA product feed is a structured file or API stream that lists a store's products with attributes such as ID, title, description, price, availability, image and landing page URL. Google Merchant Center, marketplaces and comparison sites read the feed to list products and power shopping ads, so it has to be kept in sync with what the store actually shows and sells.Professional · SEO · CMS & E-commerce
- Product SchemaProduct schema is structured data that describes a product's name, image, price, currency, availability and reviews using schema.org's Product and Offer types. Google uses it for two experiences: product snippets for pages where the product can't be bought directly, such as reviews, and merchant listings for pages where it is sold. Valid markup makes a page eligible; it doesn't guarantee display.Professional · SEO · CMS & E-commerce
- ProfilePage SchemaProfilePage schema is schema.org markup stating that a page is a profile focused on a single person or organisation, which is described in the mainEntity property as a Person or Organization. Google uses it on sites where creators share their own perspectives, such as forums, social platforms and author pages on news sites, to better understand who produced the content.Advanced · SEO · GEO
- Programmatic SEOProgrammatic SEO is the practice of generating large numbers of pages automatically by combining a structured dataset with a page template, so that each page targets one of many similar search queries. Currency converters, integration pages and location-based listings are typical examples. When pages do not offer genuinely distinct, useful data, the approach runs into Google's scaled content abuse and doorway policies.Advanced · SEO
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- Query ExpansionQuery expansion is an information retrieval technique in which a search system enriches the user's query with synonyms, word stems, spelling corrections, related terms or rewritten phrasings so that it can retrieve more relevant documents. Its purpose is to reduce missed results when the words a user types do not literally match the words used in the documents that answer the need.Advanced · SEO · GEO
- Query ParameterA query parameter is a key-value pair in the part of a URL that follows the question mark, with pairs usually separated by ampersands, as in ?color=black&page=2. It passes filtering, sorting, search or tracking information to the server or to scripts on the page. It differs from a path parameter, which identifies the resource inside the path itself. Because search engines treat every distinct parameter combination as its own URL, parameters can create duplicate content.Core · SEO · Software
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- Ranking FactorA ranking factor is a signal or input a search engine uses when ordering pages for a given query. Google says its systems look at many factors and signals across hundreds of billions of pages, but it does not publish a complete list or the weights. The broad areas Google describes are the meaning of the query, relevance, quality, usability and the searcher's context.Core · SEO
- RedirectA redirect automatically sends users and search engine crawlers from one URL to another. 301 and 308 are permanent redirects; 302 and 307 are temporary. A permanent redirect strongly signals to search engines that the new address should become the canonical one, while with a temporary redirect the original URL may stay in the index.Core · SEO
- Redirect ChainA redirect chain is when a URL reaches its final destination through several intermediate redirects instead of one, for example A to B to C. Every hop is a separate HTTP request, adding latency for users and extra work for crawlers. Googlebot follows up to 10 hops, but Google recommends not chaining at all and redirecting straight to the final URL.Professional · SEO
- Redirect LoopA redirect loop occurs when following a URL's redirects leads back to itself or to an address already visited, so no response with status 200 is ever reached. Browsers give up after a set number of hops with a 'too many redirects' error, and search engines cannot crawl the page. Loops usually come from conflicting rules across the server, CDN, application and CMS.Professional · SEO
- Referring DomainA referring domain is a unique domain that has at least one link pointing to your site. A hundred links from the same site count as one referring domain. Because it reflects the breadth of a link profile more realistically than the raw backlink total, it is a core metric in SEO tools; it is not a figure Google publishes, but a count each tool makes from its own crawl data.Professional · SEO
- Relevance ScoringRelevance scoring is how a search system expresses, as a number, how relevant a document or passage is to a particular query; results are then sorted by that number. Classic methods rely on word statistics such as TF-IDF and BM25, while modern methods use embedding similarity and cross-encoder models. Large search engines combine these scores with many other signals.Advanced · SEO · AI Visibility
- RenderingRendering is the process in which a browser or a search engine executes a page's HTML, CSS and JavaScript to produce a displayable page and its final DOM. Google renders pages in a separate step after crawling, using its Web Rendering Service (WRS) built on an up-to-date version of Chromium, and generally indexes the rendered result rather than only the raw HTML.Professional · SEO · Web Design
- Responsive ImagesResponsive images are the set of HTML techniques for describing several versions of an image, at different widths, resolutions or crops, so the browser can pick the file that best fits the screen size, pixel density and layout. The core tools are the srcset and sizes attributes on img and the picture element. The aim is to avoid sending oversized files to small screens while keeping images sharp on high-density displays.Professional · SEO · Web Design · Performance & Analytics
- Rich ResultA rich result is a Google search result that goes beyond the standard title, URL and description by adding elements such as review stars, prices, event dates, recipe details or an image carousel. Most rich results are enabled by structured data on the page; valid markup makes a page eligible but never guarantees the enhanced display.Professional · SEO
- Robots.txtRobots.txt is a plain text file published at the root of a site (for example https://example.com/robots.txt) that tells crawlers which URL paths they may crawl. It implements the Robots Exclusion Protocol, standardised as RFC 9309. It controls crawling, not indexing: a blocked URL can still appear in search results without a description if other pages link to it.Core · SEO · GEO
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- sameAs PropertysameAs is a schema.org property that gives the URL of another web page which unambiguously indicates an item's identity, such as an organization's official social profiles, its Wikidata entry or its Wikipedia article. Used in structured data, it helps search engines and AI systems connect records on different websites to the same entity. Its value is a URL, and several links can be supplied as a list.Professional · SEO · GEO
- Schema.orgSchema.org is an open project that publishes a shared vocabulary of types and properties for describing entities and their relationships on web pages. It was launched in 2011 by Google, Bing and Yahoo, with Yandex joining shortly after. It defines types such as Organization, Product and Article, all descending from Thing, plus properties such as name, author and price, and can be expressed in JSON-LD, Microdata or RDFa.Professional · SEO · GEO
- Search EngineA search engine is a software system that discovers web pages with automated programs, analyses and stores their content in an index, and ranks the results it judges most useful for each query a user types. Google, Bing and Yandex are general web search engines; vertical engines such as image, map or on-site search focus on a single type of content.Core · SEO
- Search IntentSearch intent is the underlying goal behind a search query: what the person actually wants to achieve, such as learning something, reaching a specific website, comparing options before buying, or completing an action. Because search engines shape their results around this goal, matching intent is one of the basic conditions for a page to be visible.Core · SEO · GEO
- Search QueryA search query is the exact text a person types or speaks into a search engine or AI-powered search interface, including typos, question phrasing and everyday wording. It differs from a keyword: a keyword is the abstract term a page or campaign targets and stands for many similar searches, while a query is what a real person actually entered at a specific moment.Core · SEO
- Search VolumeSearch volume is an estimate of how many times a keyword is searched per month on average in a given location and language. It is usually reported as a 12-month average and includes the keyword's close variants. It is used to compare search demand between topics, but it does not tell you directly how much traffic a page will receive.Core · SEO
- Semantic HTMLSemantic HTML is markup chosen for what content means rather than how it looks: nav for navigation, main for the primary content, h1 to h6 for headings, button for actions and an a element with an href for links. Because the structure and role of each part are stated in the code, browsers, screen readers, search engine crawlers and AI systems can understand the page without guessing from its visual styling.Core · SEO · GEO · Web Design
- Semantic SearchSemantic search is a retrieval approach that returns results based on the meaning of a query and of the content, not just on exact word matches. It accounts for synonyms, context, entities and user intent. Today it is often implemented with vector search, where text is converted into numerical vectors (embeddings) and the content closest in meaning to the query is retrieved.Professional · SEO · AI Visibility
- SEO (Search Engine Optimization)SEO (search engine optimization) is the practice of improving a website so that search engines such as Google can crawl, understand and index its pages, and show them in unpaid (organic) results for relevant queries. It combines technical work, content that answers what people actually search for, and trust signals the site earns from across the web.Core · SEO
- SEO AuditAn SEO audit is a systematic review that identifies what prevents a website from being found, understood and ranked by search engines. It checks layers such as crawlability and indexability, technical infrastructure, on-page elements, content quality, links and performance, and turns the findings into a fix list prioritised by impact.Core · SEO
- SERP (Search Engine Results Page)A SERP (search engine results page) is the page a search engine shows in response to a query. Alongside classic organic results it can include sponsored ads, featured snippets, rich results, image and video blocks, local map results, related-question boxes and AI-generated summaries such as Google's AI Overviews. Its layout varies by query, location and device.Core · SEO
- SERP FeatureA SERP feature is any element on a search results page beyond the standard blue-link result: featured snippets, related-question boxes, rich results, the local map pack, knowledge panels, image and video blocks, shopping listings and AI Overviews, among others. Each feature has its own data source, eligibility rules and degree of control available to site owners.Professional · SEO
- Site MigrationA site migration is any change to a fundamental part of a website: its domain, URL structure, protocol, platform (CMS) or hosting. When URLs change, every old address is mapped to its closest new equivalent with a permanent redirect. The goal is to carry users and accumulated search signals over to the new setup without loss, although rankings can fluctuate for a while even after a well-run move.Advanced · SEO
- Site NavigationSite navigation is the set of structures, such as the main menu, submenus, mega menus, breadcrumbs and footer links, that lets visitors and search engine crawlers move between the pages of a website. Good navigation makes the site's information architecture visible and shows people where they are and where they can go. For SEO, it provides crawlable internal links that help important pages get discovered and understood as important.Core · SEO · Web Design
- SitelinksSitelinks are additional links to other pages on the same domain that Google groups beneath a site's main search result. Google's systems generate them automatically by analysing the site's structure, and site owners cannot add or choose them directly. They appear most often for navigational searches, such as a query for a brand name, where the user is clearly looking for one specific site.Professional · SEO
- Sitemap IndexA sitemap index is an XML file that lists the locations of several XML sitemap files. Because a single sitemap is limited to 50,000 URLs and 50 MB uncompressed, large sites split their URLs across multiple sitemaps and submit them all at once through an index file whose root element is sitemapindex.Professional · SEO
- Soft 404A soft 404 is a URL that shows users a "page not found" message, or an empty page with no meaningful content, while the server responds with 200 OK instead of 404. Google detects these pages from their content, keeps them out of the index and lists them under the "Soft 404" reason in Search Console's Page indexing report. The fix is to make the status code match what the page really is.Professional · SEO
- SPA (Single-Page Application)A SPA (single-page application) is a web app model that loads one HTML document into the browser and handles every later page change by rewriting that document's content with JavaScript instead of requesting a new one. Data usually comes from APIs, and the address bar is updated through the History API. Its counterpart is the multi-page application (MPA), which fetches a fresh HTML document from the server on every navigation.Professional · SEO · Web Design · Software
- SSR (Server-Side Rendering)SSR (server-side rendering) means generating a web page's HTML on the server for each request and sending it to the browser with its content already in place. The browser can show text and links before any JavaScript runs, and search engines and other crawlers find the content directly in the HTML response. In modern frameworks SSR is usually paired with hydration, which makes the page interactive.Professional · SEO · Web Design · Software
- Structured Data (Schema Markup)Structured data is information on a page (a product, article, business or event, for example) marked up in a standardised format that search engines and other machines can interpret unambiguously. The most widely used vocabulary is schema.org, and Google recommends the JSON-LD format. Valid structured data can make a page eligible for rich results, but it does not guarantee that they will be shown.Core · SEO · GEO
- SubdomainA subdomain is a label added to the left of a domain name and defined in DNS as its own host, like "blog" in blog.example.com. Browsers and search engines treat a subdomain as a separate host: robots.txt, cookie scope and URL-prefix properties in Search Console all work at host level. Compared with a subfolder, a subdomain is more independent technically but more fragmented to manage.Professional · SEO · Security & Infrastructure
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- Taxonomy (Categories and Tags)A taxonomy is the classification system a content management system uses to group posts, pages or products by shared characteristics. The best-known examples are hierarchical categories and flat tags. Because each taxonomy term usually generates its own archive page and URL, taxonomy design directly shapes site structure, internal linking and the number of pages search engines have to crawl.Professional · SEO · CMS & E-commerce
- Technical SEOTechnical SEO is the work done on a website's infrastructure so that search engines can crawl, render and index its pages without obstacles. It covers server responses, URL structure, robots.txt, XML sitemaps, canonical tags, redirects, page speed, mobile friendliness and structured data, rather than the wording of the content itself.Core · SEO
- Thin ContentThin content is a page that offers visitors no original information, experience or function of its own, typically because it is copied from elsewhere, mass-produced from a template or created only to attract search traffic. Google addresses it through its spam policies and quality systems, and severe cases can receive a 'Thin content with little or no added value' manual action in Search Console.Core · SEO
- Topic ClusterA topic cluster is a content structure in which a pillar page covering a broad subject is connected by internal links to supporting pages that each explore one sub-question in depth. It helps visitors move through a subject and helps search engines understand how the pages relate. It is an editorial and information architecture model, not a Google ranking signal.Professional · SEO · GEO
- Topical AuthorityTopical authority is an SEO industry concept describing how a website becomes a go-to source on a subject by covering it comprehensively, consistently and credibly. It is associated with interlinked content clusters, thorough coverage of subtopics and external recognition. Google does not publish or expose a single 'topical authority' score for general web search.Professional · SEO · GEO
- Trailing SlashA trailing slash is the / character at the end of a URL path, the difference between /services/ and /services. Google treats the two forms as separate URLs. Apart from the root of a domain, which form you choose does not matter for SEO; what matters is picking one, permanently redirecting the other to it and using it consistently in internal links.Professional · SEO · Web Design
- TTFB (Time to First Byte)TTFB (Time to First Byte) is the time between the start of a navigation to a page and the moment the first byte of the server's response begins to arrive. It covers redirects, DNS lookup, connection and TLS setup, and the time the server needs to start responding. It is not a Core Web Vital; web.dev treats 0.8 seconds or less at the 75th percentile as good.Professional · SEO · Performance & Analytics
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- X-Robots-TagX-Robots-Tag is an HTTP response header that carries the same directives as the robots meta tag, but in the server's response rather than in the HTML. It is how indexing and serving rules are applied to non-HTML files such as PDFs, images and videos, and it lets you set rules in bulk at server or CDN level by file type, directory or entire hostname.Professional · SEO
- XML SitemapAn XML sitemap is a file that lists the URLs on a site you want search engines to find, optionally with the date each was last modified, in a machine-readable format defined by the sitemaps.org protocol. It helps crawlers discover pages, especially on new, large or poorly linked sites, but it does not guarantee that any listed URL will be crawled or indexed.Core · SEO
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- 200 OK200 OK is the HTTP status code a server returns when it has successfully handled a request. What the response body means depends on the method: for GET it is the requested resource itself, for POST the outcome of the action. To search engines a 200 means the content can move on to the next processing step, but it does not guarantee the page will be indexed.Core · SEO · Software
- 301 RedirectA 301 redirect is a server response with the status code 301 Moved Permanently and a Location header, telling clients that a URL has moved to a new address for good. Browsers and crawlers follow it automatically, and Google treats it as a strong signal that the target URL should become canonical. Its sibling, 308 Permanent Redirect, means the same but guarantees the request method is kept.Core · SEO
- 302 RedirectA 302 redirect is a server response with the status code 302 Found, saying the requested resource temporarily lives at another address. The user is sent to the URL in the Location header, but clients are expected to keep using the original URL in future. Google follows a 302 without treating it as a canonical signal, so the source URL usually stays in search results. 307 Temporary Redirect is its method-preserving equivalent.Core · SEO
- 304 Not Modified304 Not Modified is the HTTP status code a server returns to a conditional GET or HEAD request when the client's stored copy is still valid. The client sends back the earlier ETag in If-None-Match or a date in If-Modified-Since; if nothing has changed, the server replies with a body-less 304 and the client reuses its cached copy.Professional · SEO · Software · Performance & Analytics
- 403 Forbidden403 Forbidden is the HTTP status code meaning the server understood the request but refuses to fulfil it. If credentials were sent, the server considers them insufficient, so repeating the request with the same credentials will not help. The refusal can also have nothing to do with identity, coming instead from file permissions, IP restrictions, firewall rules or bot protection.Professional · SEO · Software · Security & Infrastructure
- 404 Not Found404 Not Found is the HTTP status code meaning the server found no current content for the requested URL, or is not willing to disclose that it exists. It does not say whether the condition is temporary or permanent. Google does not index URLs that return 404 and removes previously indexed ones; 404 responses have no effect on a site's crawl rate.Core · SEO · Software
- 410 Gone410 Gone is the HTTP status code saying a resource is no longer available and that this is most likely permanent. Unlike 404, it states explicitly that the content was removed on purpose; if the server cannot be sure the removal is permanent, it should use 404. Google handles 410 like other 4xx codes: the URL is not indexed, and is removed if it was.Professional · SEO
- 429 Too Many Requests429 Too Many Requests is the HTTP status code saying a client has sent too many requests in a given amount of time, in other words that it hit a rate limit. Defined in RFC 6585, the response may include a Retry-After header stating how long to wait. Google's crawlers treat a 429 as a sign that the server is overloaded, count it as a server error and slow down crawling.Professional · SEO · Software · Security & Infrastructure
- 500 Internal Server Error500 Internal Server Error is the generic HTTP error code meaning the server hit an unexpected condition that prevented it from fulfilling the request. It is used when no more specific 5xx code applies and says the problem lies on the server, not the client. When Google receives 500s it crawls the site more slowly, and URLs that keep failing are eventually dropped from the index.Core · SEO · Software
- 503 Service Unavailable503 Service Unavailable is the HTTP status code a server returns when it temporarily cannot handle a request because of overload or scheduled maintenance, with the condition expected to clear after some delay. The response may include a Retry-After header telling clients when to try again. For short maintenance windows it is the code that sends search engines the right message.Professional · SEO · Software
Other categories
- GEO Glossary63 termsAI Visibility · Entity · GEO · Structured Data
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- CMS & E-commerce Glossary27 termsAbandoned Cart · Checkout · CMS · CRM