SEO glossary

Short, plain definitions of the terms that come up in SEO news. Each term has its own page with the related Google updates and the latest headlines that mention it.

AI Mode: A conversational, AI-first search experience in Google Search where answers are generated and follow-up questions continue the thread.
AI Overviews: Google's AI-generated summaries shown above or among search results, with links to the pages they draw on.
Anchor text: The visible, clickable words of a link, which describe the page it points to.
Backlinks: Links from other websites pointing to a page — still one of the main signals search engines use to judge importance.
Canonical URL: The URL a search engine treats as the main version of a page that exists at several addresses.
Cloaking: Showing search engines different content from what users see, in order to manipulate rankings — a spam policy violation.
CLS (Cumulative Layout Shift): The Core Web Vital for visual stability: how much visible content moves unexpectedly while the page is in use.
Core update: A broad, announced change to how Google's main ranking systems assess content, typically several times a year.
Core Web Vitals: Google's three user-experience metrics for loading (LCP), responsiveness (INP) and visual stability (CLS), measured from real Chrome users.
Crawl budget: How many URLs a search engine is able and willing to crawl on a site in a given period.
CTR (click-through rate): The share of people who saw a result and clicked it: clicks divided by impressions.
Domain Authority: A third-party score from Moz predicting how well a domain might rank, based mainly on its links. Google does not use it.
Doorway pages: Many near-identical pages made to rank for variations of a query and funnel visitors elsewhere — a spam policy violation.
Duplicate content: The same or very similar content available at more than one URL, on one site or across several.
E-E-A-T: Experience, Expertise, Authoritativeness and Trustworthiness: the qualities Google's quality rater guidelines ask raters to assess.
Expired domain abuse: Buying an expired domain and reusing its reputation to rank low-value content unrelated to what the domain was known for.
Faceted navigation: Filters such as size, colour and price that create new URLs for every combination — a common source of crawl waste.
Featured snippet: A highlighted answer extracted from one page and shown at the top of Google's results, with a link to the source.
GEO (generative engine optimisation): Work aimed at being retrieved, cited and accurately represented in AI-generated answers, alongside ranking in classic results.
Google Business Profile: The free listing that controls how a business appears in Google Maps and the local pack — formerly Google My Business.
Google Discover: Google's personalised content feed in the Google app and on mobile, which shows articles without a search query.
Googlebot: Google's web crawler, which fetches pages for Google Search, mostly as a smartphone browser.
Helpful content system: A Google ranking system, launched in 2022, that demoted sites with a high proportion of content made for search engines rather than people.
hreflang: Annotations telling search engines which language or regional version of a page to show to which users.
IndexNow: An open protocol for telling participating search engines that URLs have been added, changed or deleted.
INP (Interaction to Next Paint): The Core Web Vital for responsiveness: how long a page takes to visibly respond to clicks, taps and key presses.
Internal links: Links from one page of a site to another page of the same site.
JavaScript SEO: Making sure content and links built with JavaScript can be rendered, crawled and indexed by search engines.
Keyword cannibalisation: Several pages on one site competing for the same query, so none of them ranks as well as one strong page would.
Knowledge Graph: Google's database of entities — people, places, organisations, things — and the relationships between them.
LCP (Largest Contentful Paint): The Core Web Vital for loading: when the largest image or text block in the viewport finishes rendering.
Link spam: Links created to manipulate rankings: bought links, link exchanges, private blog networks and similar schemes.
llms.txt: A proposed plain-text file at a site's root that gives AI models a curated, Markdown map of the site's most useful content.
Local pack: The map and short list of businesses Google shows for searches with local intent.
Log file analysis: Reading a server's access logs to see exactly which URLs search engine crawlers request, and how often.
Manual action: A penalty applied by a person at Google after reviewing a site against the spam policies, reported in Search Console.
Mobile-first indexing: Google using the mobile version of a page's content for indexing and ranking.
NAP consistency: Keeping a business's Name, Address and Phone number identical everywhere it is listed online.
noindex: A robots meta tag or HTTP header telling search engines not to show a page in results.
Orphan pages: Pages no other page on the site links to, so crawlers and visitors struggle to find them.
Page experience: Google's collective term for signals about how pleasant a page is to use: Core Web Vitals, HTTPS, mobile-friendliness and intrusive interstitials.
PageRank: Google's original algorithm for judging a page's importance from the links pointing to it, named after co-founder Larry Page.
People Also Ask: The expandable box of related questions in Google's results, each opening to a short answer from a web page.
Programmatic SEO: Generating large numbers of pages from a database and templates, each targeting a specific long-tail query.
Quality rater guidelines: Google's public handbook for the people who rate search results to help it evaluate changes to its systems.
Redirects (301 and 302): Server responses that send visitors and crawlers from one URL to another — permanent (301, 308) or temporary (302, 307).
nofollow, sponsored and ugc: Link attributes that tell search engines a link is not an editorial endorsement: rel="nofollow", rel="sponsored" and rel="ugc".
Reviews system: Google's ranking system for review content, rewarding first-hand experience and original analysis over summaries of manufacturer claims.
robots.txt: A file at a site's root telling crawlers which URLs they may request. It controls crawling, not indexing.
Scaled content abuse: Producing many pages primarily to manipulate rankings, with little value to readers — however they are made.
Search Console: Google's free tool for site owners to see search performance, indexing status, manual actions and technical issues.
Search intent: What a searcher is actually trying to do with a query — learn, go somewhere, compare or buy.
SERP features: Anything on a results page beyond the ten blue links: AI Overviews, featured snippets, People Also Ask, local packs, carousels and more.
Site migration: Any large change to a site's URLs, domain, platform or structure that search engines must re-learn.
Site reputation abuse: Publishing third-party content on an established site mainly to exploit that site's ranking signals — sometimes called parasite SEO.
Soft 404: A page that tells visitors it does not exist (or has nothing on it) but answers with a 200 "OK" status instead of 404.
Spam update: An update to Google's spam-detection systems that enforces its spam policies, usually rolling out over a few days.
Structured data: Machine-readable markup, usually schema.org in JSON-LD, describing what a page is about and making it eligible for rich results.
Thin content: Pages with little original value: doorway pages, auto-generated text, scraped copy or affiliate pages that add nothing.
Topical authority: An industry term for a site being recognised as a thorough, trustworthy source on a subject, built by covering it in depth.
XML sitemap: A file listing the URLs a site wants search engines to know about, with optional last-modified dates.
YMYL (Your Money or Your Life): Topics where poor information could harm someone's health, finances, safety or wellbeing — held to a higher standard by Google.
Zero-click search: A search that ends on the results page, with no click to any website.