Glossary
The SEO glossary, in plain English
88 terms from technical SEO, content, performance and AI search, each with an example and what it means for a WordPress site.
# 5
- 301 redirectA 301 redirect is an HTTP response telling browsers and search engines that a URL has moved permanently to a new address, so links and rankings should transfer to the new URL.
- 302 redirectA 302 redirect is an HTTP response that sends visitors to a different URL temporarily, signaling to search engines that the original URL should stay indexed.
- 404 errorA 404 error is the HTTP Not Found status a server returns when a requested URL does not exist. Some 404s are normal; broken links to them and lost backlinks are what cost you.
- 410 Gone410 Gone is an HTTP status code that tells browsers and search engines a URL has been removed on purpose and will not come back, a more explicit version of a 404.
- 503 Service Unavailable503 Service Unavailable is an HTTP status code meaning the server cannot handle the request right now, usually due to maintenance or overload, and should be tried again later.
A 5
- AI ModeAI Mode is Google's conversational search experience, launched in the US in 2025, that answers complex questions with an AI response, accepts follow-ups, and links to web sources.
- AI OverviewsAI Overviews are AI-generated summaries that Google shows at the top of some search results, answering the query directly and linking to the web pages used as sources.
- Alt textAlt text is the written description of an image in its HTML alt attribute. Screen readers read it aloud, browsers show it when the image fails to load, and search engines use it.
- Anchor textAnchor text is the visible, clickable text of a hyperlink. Search engines use it as a description of the page being linked to.
- Answer engine optimization (AEO)Answer engine optimization (AEO) is the practice of structuring content so AI assistants such as ChatGPT, Perplexity, and Google's AI features can find, understand, and cite it in their answers.
B 2
- BacklinksBacklinks are links from other websites pointing to pages on your site. Search engines treat them as signals of trust and relevance, and they remain an important ranking factor.
- BreadcrumbsBreadcrumbs are a secondary navigation trail, such as Home > Guides > Coffee, that shows where a page sits in a site's hierarchy and links back up to each parent level.
C 9
- Canonical URLA canonical URL is the preferred address of a page, declared with a rel="canonical" link tag, that tells search engines which of several duplicate URLs to index and credit.
- CDNA CDN (content delivery network) is a network of servers in many locations that stores copies of a site's files and serves each visitor from a nearby location to cut load time.
- Character encodingCharacter encoding is the system that maps a page's bytes to readable characters. Declaring it, almost always as UTF-8, lets browsers and crawlers display text correctly.
- Click-through rate (CTR)Click-through rate (CTR) is the percentage of people who click a result after seeing it, calculated as clicks divided by impressions. In SEO it is measured per page and query.
- Content decayContent decay is the gradual decline in search traffic and rankings of a page that once performed well, usually because it aged, competitors improved, or intent shifted.
- Core Web VitalsCore Web Vitals are three Google metrics for real-user experience: Largest Contentful Paint (loading), Interaction to Next Paint (responsiveness), and Cumulative Layout Shift (visual stability).
- Crawl budgetCrawl budget is the number of URLs a search engine is able and willing to crawl on a site over a period of time, set by server capacity and how much the engine wants the content.
- CrawlingCrawling is the process by which search engine bots such as Googlebot discover URLs and download their content, mainly by following links and reading sitemaps.
- Cumulative Layout Shift (CLS)Cumulative Layout Shift (CLS) is a Core Web Vital that scores how much visible content moves unexpectedly while a page is open, such as text jumping when an image loads.
D 3
- DisavowDisavowing links means submitting a file through Google Search Console that asks Google to ignore specific backlinks or entire domains when assessing your site.
- DoctypeA doctype is the <!DOCTYPE html> declaration at the very top of an HTML document that tells browsers to render the page in standards mode rather than legacy quirks mode.
- Duplicate contentDuplicate content is the same or nearly the same content reachable at more than one URL, on one site or across sites. Search engines index one version and filter out the rest.
E 1
F 3
- Faceted navigationFaceted navigation is a set of filters on a listing page, such as color, size, brand, and price, that narrows results and often creates a new URL for every combination.
- FaviconA favicon is the small icon that identifies a website in browser tabs, bookmarks, and mobile search results, declared with a link rel="icon" tag in the page head.
- Featured snippetA featured snippet is a highlighted box in Google results that quotes a short answer from one web page, as a paragraph, list, or table, with a link to the source.
G 4
- Generative engine optimizationGenerative engine optimization (GEO) is the practice of making content more likely to be used and cited by AI systems that generate answers, such as ChatGPT, Perplexity, and Google AI Mode.
- Google Business ProfileA Google Business Profile is a free listing, formerly called Google My Business, that shows a business's details, hours, photos, and reviews in Google Maps and local search.
- Google DiscoverGoogle Discover is a personalized feed of articles and videos in the Google app and on Google's mobile homepage, shown based on a user's interests rather than a typed query.
- Google Search ConsoleGoogle Search Console is a free service from Google that shows how a site appears in Google Search, including queries, clicks, indexing status, and technical problems.
H 4
- H1 tagAn H1 tag is the top-level HTML heading element (<h1>) on a page, normally used for the main visible title that tells readers and search engines what the page is about.
- HreflangHreflang is an attribute on link tags that tells search engines which language and regional versions of a page exist, so each searcher is shown the version meant for them.
- HTTP status codesHTTP status codes are three-digit numbers a server returns with every response, telling browsers and crawlers whether the request succeeded, was redirected, or failed.
- HTTPSHTTPS is the encrypted version of HTTP. It uses TLS to protect data sent between a browser and a website, and Google uses it as a lightweight ranking signal.
I 7
- Image SEOImage SEO is the practice of making images discoverable and understandable to search engines, through alt text, file names, formats, sizing, and markup, while keeping pages fast.
- Image sitemapAn image sitemap is an XML sitemap, or an extension of one, that lists the images on each page with image:image tags so search engines can discover them for image search.
- Index bloatIndex bloat is when a search engine has indexed far more of a site's URLs than the site has pages worth ranking, usually thin archives, parameter URLs, and duplicates.
- IndexingIndexing is the process in which a search engine analyzes a crawled page and stores it in its index, the database it draws on to answer searches. Only indexed pages can rank.
- IndexNowIndexNow is an open protocol that lets a website notify participating search engines, such as Bing and Yandex, immediately when a URL is added, updated, or deleted.
- Interaction to Next Paint (INP)Interaction to Next Paint (INP) is a Core Web Vital that measures how quickly a page visibly responds to clicks, taps, and key presses across the whole visit.
- Internal linkingInternal linking is the practice of linking from one page on a site to another page on the same site, helping visitors navigate and search engines discover and understand pages.
J 2
- JavaScript SEOJavaScript SEO is the practice of making sure pages that rely on JavaScript to build content, links, or metadata can still be crawled, rendered, and indexed by search engines.
- JSON-LDJSON-LD (JavaScript Object Notation for Linked Data) is a W3C format for expressing structured data as JSON, and the format Google recommends for schema.org markup.
K 3
- Keyword cannibalizationKeyword cannibalization is when two or more pages on the same site target the same search query and intent, splitting signals so that none ranks as well as one strong page would.
- Keyword researchKeyword research is the process of finding the words and phrases people type into search engines about a topic, then judging which are worth targeting with a page.
- Knowledge panelA knowledge panel is an information box in Google's results about a person, organization, place, or thing, built from Google's Knowledge Graph of known entities.
L 5
- Largest Contentful Paint (LCP)Largest Contentful Paint (LCP) is a Core Web Vital that measures the time from when a page starts loading until its largest visible image or text block is rendered.
- Lazy loadingLazy loading is a technique that defers loading off-screen images, iframes, and other resources until the user scrolls near them, reducing initial page weight and load time.
- llms.txtllms.txt is a proposed convention: a Markdown file at a site's root (/llms.txt) that summarizes the site and links its most important pages for large language models to read.
- Local SEOLocal SEO is the work of making a business visible in searches with local intent, such as "dentist near me", across Google Maps, the local pack, and regular results.
- Long-tail keywordsLong-tail keywords are specific, usually longer search phrases with low individual search volume that are easier to rank for and often match a clear need.
M 3
- Meta descriptionA meta description is an HTML meta tag that summarizes a page's content. Search engines often, but not always, show it as the snippet text below the result title.
- Meta robots tagThe meta robots tag is an HTML element in a page's head that gives search engines page-level instructions such as noindex, nofollow, noarchive, and snippet limits.
- Mobile-first indexingMobile-first indexing means Google predominantly crawls and indexes the mobile version of a page and uses that version's content for ranking, including desktop results.
N 3
- NAP consistencyNAP consistency means a business's name, address, and phone number are written the same way on its website, Google Business Profile, directories, and social profiles.
- NofollowNofollow is a rel attribute value on a link (rel="nofollow") that asks search engines not to pass ranking credit through it. Since 2019 Google treats it as a hint rather than a strict rule.
- NoindexNoindex is a robots directive, set in a meta tag or HTTP header, that tells search engines they may crawl a page but must not include it in search results.
O 2
- Open GraphOpen Graph is a protocol of meta tags (og:title, og:description, og:image and others) that controls the title, description, and image shown when a link is shared on social platforms.
- Orphan pageAn orphan page is a page on a website that no other page on the same site links to, so visitors cannot navigate to it and crawlers can find it only through sitemaps or external links.
P 4
- Page speedPage speed is how quickly a web page loads, displays its content, and responds to input, measured with metrics such as TTFB, LCP, and INP rather than one single number.
- PaginationPagination is splitting a long list of items, such as blog posts or products, across a numbered series of pages (/page/2/, /page/3/) linked to one another.
- People Also AskPeople Also Ask (PAA) is a Google results feature showing related questions that expand to reveal a short answer from a web page with a link to the source.
- PermalinkA permalink is the permanent URL of a specific post, page, or archive. In WordPress the term also refers to the site-wide structure that decides how those URLs are built.
Q 1
R 3
- Redirect chainA redirect chain is a sequence of two or more redirects between the first requested URL and the final page, such as A to B to C, which slows loading and crawling.
- Rich resultsRich results are search listings that show more than a title, URL, and snippet, such as star ratings, prices, images, or event dates, usually generated from structured data.
- robots.txtrobots.txt is a plain-text file at the root of a domain that tells web crawlers which URL paths they are allowed to request. It controls crawling, not indexing.
S 8
- Scaled content abuseScaled content abuse is a Google spam policy, introduced in March 2024, against generating many pages mainly to manipulate rankings rather than help people, however they are made.
- Schema markupSchema markup is structured data that uses the schema.org vocabulary to describe what a page contains, such as an article, product, or event, in a form machines can read directly.
- Search intentSearch intent is the underlying goal a person has when typing a query, such as learning something, reaching a specific site, comparing options, or making a purchase.
- SERPA SERP (search engine results page) is the page a search engine shows in response to a query, containing organic results, ads, and features such as AI Overviews and local packs.
- Server-side renderingServer-side rendering (SSR) is generating a page's complete HTML on the server for each request, so browsers and crawlers receive the content without having to run JavaScript first.
- Sitemap indexA sitemap index is an XML file that lists the locations of other sitemap files, letting a site split its URLs across many smaller sitemaps and submit them with one URL.
- Soft 404A soft 404 is a URL that returns a success status (200 OK) but shows content Google judges to be an error, empty, or missing page, so Google treats it as not found.
- Sponsored and UGC linksSponsored and UGC links are links marked rel="sponsored" (paid or affiliate) or rel="ugc" (user-generated content), attributes Google has recognized as hints since 2019.
T 6
- Thin contentThin content is a page that offers little or no original value to a visitor, such as near-empty pages, doorway pages, scraped or spun text, or affiliate pages with nothing added.
- Time to First Byte (TTFB)Time to First Byte (TTFB) is the time between a browser requesting a page and receiving the first byte of the response, covering redirects, DNS, connection, and server work.
- Title tagA title tag is the HTML <title> element that names a page. Search engines usually show it as the clickable headline of a result, and browsers show it in the tab.
- Topic clustersA topic cluster is a group of pages on one subject: a broad pillar page that links to detailed pages on each subtopic, which link back to the pillar and to each other.
- Topical authorityTopical authority is the SEO idea that a site which covers a subject thoroughly and well becomes a more trusted source for queries about that subject.
- Twitter cardA Twitter card is the preview X (formerly Twitter) shows for a shared link, controlled by twitter: meta tags such as twitter:card, twitter:title, and twitter:image.
U 1
V 1
X 2
- X-Robots-TagThe X-Robots-Tag is an HTTP response header that carries robots directives such as noindex or nosnippet, letting you control indexing of any file type, not just HTML pages.
- XML sitemapAn XML sitemap is a machine-readable file that lists the URLs on a site you want search engines to crawl and index, usually with the date each page last changed.