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299 terms

SEO glossary

Every SEO term you will meet, explained in plain English: what it means, why it matters for rankings and what to do about it. From the basics of crawling and indexing to AI search, with every technique labelled white, grey or black hat.

  • White hatWithin Google’s guidelines. Safe to use.
  • Grey hatNot banned outright, but easy to tip into spam. Use with care.
  • Black hatAgainst Google’s spam policies. Risks a manual action or a ranking drop.

White hat vs grey hat vs black hat SEO

SEO basics: start here

SEO terms by topic

SEO terms A to Z

#

301 redirect
A 301 redirect permanently sends visitors and search engines from one URL to another and tells Google the new URL should be indexed.
302 redirect
A 302 redirect temporarily sends visitors to another URL while telling search engines to keep the original URL indexed.
404 error
A 404 error is the HTTP status a server returns when a requested page does not exist. It is normal, but broken links to 404s are worth fixing.
5xx server errors
5xx server errors are HTTP status codes meaning the server failed to handle a request. Persistent ones make Google crawl less and drop pages.

A

Above the fold
Above the fold is the part of a page visible without scrolling. It should show the main content quickly, not a wall of ads or banners.
AI citations
AI citations are the links an AI assistant shows as sources for its answer. Being cited means your page helped build the answer.
AI crawlers (GPTBot, ClaudeBot)
AI crawlers are bots that AI companies use to collect web content for model training or for AI search answers, such as GPTBot and ClaudeBot.
AI Overviews
AI Overviews are AI-generated summaries that Google shows at the top of some search results, with links to the web pages they draw on.
AI SEO agent
An AI SEO agent is an AI assistant that uses SEO tools by itself to research, analyse and report, working through multiple steps towards a goal.
AI visibility
AI visibility is how often and how prominently AI assistants such as ChatGPT, Gemini, Claude and Perplexity mention your brand or cite your site.
AI-generated content
AI-generated content is text, images or other media produced with generative AI tools. Google judges it by quality, not by how it was made.
Algorithmic penalty
An algorithmic penalty is a ranking drop caused by Google’s automated systems, not a human reviewer, with no notice in Search Console.
Alt text
Alt text is a short written description of an image in its HTML alt attribute. It helps screen reader users and tells search engines what the image shows.
Anchor text
Anchor text is the visible, clickable text of a link. Search engines read it as a clue to what the linked page is about.
Answer engine optimization (AEO)
Answer engine optimization (AEO) is optimising content so search features and AI assistants use it to answer questions directly.
Apple Business Connect
Apple Business Connect is Apple’s free tool for businesses to claim and manage how their place appears in Apple Maps and other Apple apps.
Article spinningBlack hat
Article spinning is rewriting existing content with synonyms or software to pass it off as new, which Google treats as scraping or scaled content abuse.
Automated queriesBlack hat
Automated queries are searches sent to Google by bots without permission, covered by Google’s machine-generated traffic policy.
Average position
Average position is the mean of your topmost ranking each time your site appeared in Google results, as reported in Search Console.

B

Backlink
A backlink is a link from another website to yours. Search engines treat backlinks as votes of trust and use them to rank and discover pages.
Bing Places
Bing Places for Business is Microsoft’s free tool for managing how a business appears in Bing search and Bing Maps.
Bing SEO
Bing SEO is optimising a site to rank in Microsoft Bing, whose index also feeds other search services and AI tools.
Bing Webmaster Tools
Bing Webmaster Tools is Microsoft’s free console for site owners. It shows Bing search performance, indexing and crawl data, and supports IndexNow.
Black hat SEOBlack hat
Black hat SEO is the use of tactics that break search engines’ spam policies, such as paid links, cloaking or keyword stuffing, to rank faster.
Bounce rate
Bounce rate in GA4 is the share of sessions that were not engaged. It equals 100% minus engagement rate.
Brand mentions
Brand mentions are references to your brand name on other websites or in AI answers, with or without a link to your site.
Branded keywords
Branded keywords are searches that include a brand or product name, such as "notion templates" or "tesla model 3 range".
Breadcrumbs
Breadcrumbs are a row of links showing where a page sits in a site’s hierarchy, such as Home > Shoes > Running. They help users and search engines.
Broken link buildingWhite hat
Broken link building means finding broken links on other sites and suggesting your relevant page as the replacement. It is a white hat tactic.

C

Canonical tag
A canonical tag is a link element that tells search engines which URL is the main version of a page when duplicates exist.
CDN (content delivery network)
A CDN (content delivery network) is a network of servers around the world that caches and serves your site from locations close to each visitor.
ChatGPT search
ChatGPT search is the feature that lets ChatGPT search the web and answer with up-to-date information and links to its sources.
Click-through rate (CTR)
Click-through rate (CTR) is the share of impressions that become clicks: clicks divided by impressions. It shows how often searchers choose your result.
Clickbait titlesGrey hat
Clickbait titles promise more than the page delivers to win clicks. Compelling titles are fine; misleading ones are grey hat and can backfire.
Clicks
Clicks count how many times someone clicked a search result that took them to your site. Search Console reports them by query, page, device and country.
Clickstream data
Clickstream data records the pages and clicks of a panel of users. SEO tools use it to estimate search volume, clicks and traffic.
Client-side rendering (CSR)
Client-side rendering (CSR) sends a near-empty HTML page and builds the content in the browser with JavaScript, which crawlers must run to see it.
CloakingBlack hat
Cloaking is showing search engines different content from what users see in order to manipulate rankings, which breaks Google’s spam policies.
Comment spamBlack hat
Comment spam is posting links in blog comments, forums or profiles to gain backlinks, which breaks Google’s link spam and user-generated spam policies.
Commercial intent
Commercial intent is when a searcher is researching before buying, comparing products, brands or services with searches like "best" or "vs".
Comparison pages
Comparison pages compare two or more products or options side by side, such as “X vs Y” or “X alternatives”, to help people choose.
Content audit
A content audit is a review of every page on a site, with data, to decide which to keep, update, merge, redirect or remove.
Content brief
A content brief is a document that tells a writer what a page should cover, who it is for, which keywords it targets and what it must include.
Content decay
Content decay is the gradual decline in a page’s rankings and organic traffic over time, after an initial period of good performance.
Content freshness
Content freshness is how recent and up to date a page is. Google ranks fresher content higher for queries where recency matters.
Content gap
A content gap is a topic or keyword your audience searches for that your site doesn’t cover, often one your competitors already rank for.
Content marketing
Content marketing is creating and sharing useful content, such as articles, guides, videos and tools, to attract and keep customers.
Content optimizationWhite hat
Content optimization is improving a page’s content so it better matches search intent, covers the topic fully and earns more clicks and rankings.
Content pruningWhite hat
Content pruning is removing, merging or redirecting low-value pages so a site’s remaining content is stronger and easier to crawl.
Content refreshWhite hat
A content refresh is a substantial update of an existing page to make it current, accurate and more useful, so it regains or improves rankings.
Core Web Vitals
Core Web Vitals are Google’s three metrics for real-world page experience: Largest Contentful Paint, Interaction to Next Paint and Cumulative Layout Shift.
Cost per click (CPC)
Cost per click (CPC) is what advertisers pay for one click on a search ad. In SEO, a keyword’s CPC hints at how commercially valuable it is.
Crawl budget
Crawl budget is the set of URLs Google can and wants to crawl on a site. It only becomes a constraint on very large or fast-changing sites.
Crawl depth
Crawl depth is how many clicks a page is from the homepage. Deep pages are found and crawled less often than shallow ones.
Crawling
Crawling is how search engines discover pages: automated bots fetch URLs and follow the links on them to find more pages.
CTR manipulationBlack hat
CTR manipulation is using bots or paid clickers to search for a keyword and click your result, to fake user signals. It breaks Google’s rules.
Cumulative Layout Shift (CLS)
Cumulative Layout Shift (CLS) is a Core Web Vital that measures how much content moves unexpectedly while a page is used. Good is 0.1 or less.

D

Deindexing
Deindexing is when pages or a whole site are removed from a search engine’s index, so they no longer appear in results at all.
Digital PRWhite hat
Digital PR is earning coverage and links from news sites, blogs and online publications by giving journalists stories, data or expert comment.
Disavow tool
The disavow tool lets you ask Google to ignore specific links to your site. Google says most sites never need it and it can harm if misused.
Dofollow link
A dofollow link is a normal link with no rel="nofollow", "sponsored" or "ugc" value, so it can pass ranking credit to the page it points to.
Domain Authority (DA)
Domain Authority (DA) is Moz’s 1–100 score predicting how well a website might rank, based mainly on its links. Google does not use it.
Domain Rating (DR)
Domain Rating (DR) is Ahrefs’ 0–100 score of the strength of a website’s backlink profile. It is a third-party metric, not used by Google.
Doorway pagesBlack hat
Doorway pages are near-identical pages or sites built to rank for many similar searches and funnel visitors to one destination, against Google’s policies.
Duplicate content
Duplicate content is the same or very similar content available at more than one URL, on one site or across sites. Google picks one version to show.

E

E-E-A-T
E-E-A-T stands for experience, expertise, authoritativeness and trustworthiness: the qualities Google’s quality raters look for in content.
Ecommerce SEO
Ecommerce SEO is optimising an online shop’s category and product pages to rank in search, while controlling filters, duplicates and stock changes.
Editorial links
Editorial links are backlinks a writer or editor chooses to give because your content is worth citing, without payment or a link exchange.
Engagement rate
Engagement rate in GA4 is the share of sessions that were engaged: lasted 10+ seconds, had a key event, or had 2+ page or screen views.
Enterprise SEO
Enterprise SEO is SEO for very large sites and organisations, where scale, templates, many teams and governance shape the work.
Entity
An entity is a distinct, identifiable thing, such as a person, place, organisation or product, that search engines and AI models recognise.
Evergreen content
Evergreen content is content that stays relevant and useful for a long time, such as how-to guides and explainers, rather than news.
Expired domain abuseBlack hat
Expired domain abuse is buying a lapsed domain and using its old reputation to rank low-value or unrelated content, against Google’s spam policies.
Expired domainsGrey hat
Expired domains are domain names their owner let lapse. Reusing one for a real project is fine; buying it to exploit its old links is spam.

F

Faceted navigation
Faceted navigation lets visitors filter a list by attributes such as size, colour or price, and can create huge numbers of crawlable URLs.
Fake reviewsBlack hat
Fake reviews are reviews by people who were not real customers, or that misrepresent their experience. They break Google’s policies and US FTC rules.
FAQ page
An FAQ page lists common questions about a product, service or topic with short answers, to help users and answer search queries.
Featured snippet
A featured snippet is a highlighted extract from a web page shown near the top of Google’s results to answer the query directly, with a link to the source.

G

Generative engine optimization (GEO)
Generative engine optimization (GEO) is the practice of improving how often AI-generated answers mention your brand and cite your pages.
Geo-grid rank tracking
Geo-grid rank tracking checks your Google Maps ranking from many points in a grid around an area, showing how your local visibility changes by location.
Google AI Mode
Google AI Mode is a conversational search mode where a Gemini model answers your query in full, with follow-up questions and links to sources.
Google algorithm update
A Google algorithm update is a change to how Google ranks results. Big ones, like core and spam updates, are announced and can move rankings sharply.
Google Analytics 4 (GA4)
Google Analytics 4 (GA4) is Google’s free web and app analytics tool. It measures visits as events and reports where users come from and what they do.
Google Autocomplete
Google Autocomplete predicts what you are searching for as you type, suggesting full queries based on real searches, location and language.
Google Business Profile
Google Business Profile is Google’s free listing for local businesses, shown in Maps and the local pack with hours, reviews, photos and directions.
Google Business Profile categories
Google Business Profile categories describe what a business is, such as “Plumber”. The primary category is a key signal for local rankings.
Google core update
A Google core update is a broad change to Google’s main ranking systems, released several times a year, that can move rankings for many sites.
Google Discover
Google Discover is a personalised feed of articles and videos in the Google app and on mobile, shown by interest without a search query.
Google Maps SEO
Google Maps SEO is optimising your business so it ranks higher in Google Maps searches, mainly through your Google Business Profile and reviews.
Google penalty recovery
Google penalty recovery is the process of finding and fixing spam policy breaches so a site regains rankings after a manual action or demotion.
Google Search Console
Google Search Console is Google’s free tool that shows how your site performs in Google Search and flags indexing, security and spam problems.
Google spam policies
Google’s spam policies list the practices that can get a site demoted or removed from Google Search, from cloaking and link spam to scaled content abuse.
Googlebot
Googlebot is Google’s web crawler. It fetches pages so Google Search can index them, using a smartphone crawler for most sites.
Grey hat SEOGrey hat
Grey hat SEO covers tactics that are not banned outright but sit close to Google’s spam policies and can become spam when overdone.
Grounding
Grounding is tying an AI model’s answer to real, retrievable sources, such as search results, so it is current and can be checked.
Guest postingGrey hat
Guest posting is writing an article for another site, often with a link back. It is fine for exposure; done at scale for links, it is a link scheme.

H

H1 tag
An H1 tag is the main heading of a web page. It tells readers and search engines what the page is about, and most pages should have one.
Hacked content and injected spamBlack hat
Hacked content is spam pages, links or redirects placed on a site without the owner’s permission by exploiting a security hole.
HARO and journalist requestsWhite hat
HARO and other journalist request services send reporters’ requests for expert sources, so you can earn quotes, mentions and editorial links.
Head terms (short-tail keywords)
Head terms are short, broad, high-volume keywords like "shoes" or "insurance". They bring the most searches but are the hardest to rank for.
Header tags (H1–H6)
Header tags (H1–H6) are HTML headings that structure a page into sections, helping readers scan and search engines understand the content.
Heading hierarchy
Heading hierarchy is the logical order of H1 to H6 headings on a page, so sections nest correctly and readers and crawlers can follow the outline.
Helpful content
Helpful content is Google’s term for people-first content made to help readers, not to rank. Since 2024 it is assessed by Google’s core systems.
Hidden text and linksBlack hat
Hidden text and links are words or links placed on a page so search engines see them but visitors cannot, a breach of Google’s spam policies.
Hreflang
Hreflang is an annotation that tells search engines which language or regional version of a page to show to which searchers.
HSTS (Strict-Transport-Security)
HSTS is a response header that tells browsers to only connect to a site over HTTPS, so they never load it over insecure HTTP.
HTML sitemap
An HTML sitemap is a normal web page that links to a site’s main sections and pages, mainly to help visitors and crawlers navigate.
HTTP status codes
HTTP status codes are three-digit numbers a server returns with each response to say whether a request worked, moved or failed.
HTTPS
HTTPS is the encrypted version of HTTP. It protects data between browser and site, and Google uses it as a lightweight ranking signal.

I

Image pack
An image pack is a row or block of image results inside Google’s main search results, linking to Google Images and the source pages.
Image SEO
Image SEO is optimising images so they load fast, are understood by search engines and can rank in Google Images and image results.
Impressions
Impressions count how often a link to your site appeared in search results that someone viewed, whether or not they clicked it.
Index bloat
Index bloat is when a search engine indexes many more of a site’s pages than it should, most of them low-value, duplicate or unintended URLs.
Indexing
Indexing is when a search engine analyses a crawled page and stores it in its index, so it becomes eligible to appear in search results.
IndexNow
IndexNow is an open protocol that lets a site notify search engines such as Bing and Yandex the moment a URL is added, changed or deleted.
Information gain
Information gain is the new, useful information a page adds beyond what other pages on the same topic already say.
Informational intent
Informational intent is when a searcher wants to learn something, such as how to do a task or what a term means, rather than buy or visit a site.
Interaction to Next Paint (INP)
Interaction to Next Paint (INP) is a Core Web Vital that measures how quickly a page responds to clicks, taps and key presses. Good is 200 ms or less.
Internal links
Internal links are links from one page on your site to another. They help visitors navigate, help crawlers find pages and spread link authority.
International SEO
International SEO is optimising a site to rank in several countries or languages, using the right URL structure, hreflang and localised content.

J

JavaScript SEO
JavaScript SEO is the work of making sure search engines can crawl, render and index content and links that a site builds with JavaScript.
JSON-LD
JSON-LD is a JSON-based format for structured data, placed in a script tag. It is the format Google recommends for schema markup.

K

Key events (conversions)
Key events are the GA4 events you mark as important to your business, such as a purchase or sign-up. Google renamed conversions to key events in 2024.
Keyword
A keyword is a word or phrase people type into a search engine. In SEO, it’s the query you want a page to rank for.
Keyword cannibalization
Keyword cannibalization is when several pages on one site target the same keyword and intent, so they compete and none ranks as well as it could.
Keyword clustering
Keyword clustering is grouping keywords that share intent and search results, so each group can be targeted by one page.
Keyword density
Keyword density is how often a keyword appears on a page as a share of total words. It isn’t a ranking target; Google has no ideal density.
Keyword difficulty
Keyword difficulty is an SEO tool’s 0-100 estimate of how hard it is to rank on Google’s first page for a keyword, based on the pages already there.
Keyword gap
A keyword gap is the set of keywords your competitors rank for and you don’t. Keyword gap analysis finds them so you can target them.
Keyword mapping
Keyword mapping is assigning target keywords to specific pages on your site, so every page has a clear focus and no two pages compete.
Keyword ranking
A keyword ranking is the position a page holds in search results for a given query, in a given place and on a given device.
Keyword research
Keyword research is finding the search terms your audience uses, then judging which ones are worth targeting by demand, difficulty and intent.
Keyword seasonality
Keyword seasonality is the regular rise and fall of searches for a keyword through the year, such as "sunscreen" in summer or "advent calendar" in autumn.
Keyword stuffingBlack hat
Keyword stuffing is filling a page with keywords, numbers or place names in an unnatural way to manipulate rankings, against Google’s spam policies.
Keyword trend
A keyword trend shows how searches for a keyword change over time, usually month by month, so you can spot growth, decline and seasonal peaks.
Knowledge Graph
The Knowledge Graph is Google’s database of entities and the facts and relationships between them, used to power knowledge panels and answers.
Knowledge panel
A knowledge panel is the information box Google shows for a well-known person, organisation, place or thing, drawn from its Knowledge Graph.

L

Landing page
A landing page is the first page a visitor arrives on. In SEO it is the page that ranks and receives the click from search results.
Lang attribute
The lang attribute declares the language of a page’s content, usually on the <html> element, for browsers, screen readers and translation tools.
Large language model (LLM)
A large language model (LLM) is an AI model trained on huge amounts of text to predict and generate language, such as GPT, Gemini or Claude.
Largest Contentful Paint (LCP)
Largest Contentful Paint (LCP) is a Core Web Vital that measures when the largest image or text block in the viewport appears. Good is 2.5 seconds or less.
Lazy loading
Lazy loading delays loading images, iframes or other content until they are about to scroll into view, which speeds up the first load of a page.
Lighthouse
Lighthouse is Google’s open-source tool that tests a page in a lab and scores its performance, accessibility, best practices and SEO.
Link buildingWhite hat
Link building is the work of getting other websites to link to yours, to earn referral traffic and the trust that helps pages rank.
Link equity (link juice)
Link equity, or link juice, is the ranking value a link passes from one page to another, based on the linking page’s authority and relevance.
Link exchangesGrey hat
A link exchange is an agreement between sites to link to each other. Occasional relevant swaps are fine; excessive ones are link spam.
Link farmsBlack hat
A link farm is a group of sites or pages that exist mainly to link to each other or to anyone who joins, in order to inflate rankings.
Link intersect
Link intersect finds websites that link to several of your competitors but not to you. Those sites are your most likely link prospects.
Link profile
A link profile is the full set of backlinks pointing to a site: who links, how many, with what anchors and attributes, and how it changes over time.
Link reclamationWhite hat
Link reclamation is recovering backlinks you have lost or that point to broken URLs, by fixing pages, adding redirects or asking sites to update links.
Link schemesBlack hat
A link scheme is any attempt to create links mainly to manipulate rankings, such as buying, swapping or automating links, which is Google’s link spam.
Link velocity
Link velocity is how fast a site gains or loses backlinks over time. It is a useful monitoring metric, not a confirmed Google ranking factor.
LLM SEO
LLM SEO is optimising your content and brand so large language models such as ChatGPT, Gemini and Claude mention and cite you in their answers.
llms.txt
llms.txt is a proposed Markdown file at a site’s root that summarises its content for AI tools. Google Search ignores it.
Local citations
A local citation is any online mention of a business’s name, address and phone number, such as a directory listing or a review site profile.
Local landing pages
Local landing pages are pages on your site for a specific location or service area, giving local details customers and search engines need.
Local pack (map pack)
The local pack is the block of map and business listings Google shows for local searches, usually three businesses from Google Maps.
Local ranking factors
Local ranking factors decide which businesses Google shows in Maps and the local pack. Google names three: relevance, distance and prominence.
LocalBusiness schema
LocalBusiness schema is structured data that describes a business’s name, address, phone, hours and more in a format search engines can read.
Log file analysis
Log file analysis is reviewing your server’s access logs to see exactly which URLs search engine bots requested, when and with what result.
Long-tail keywords
Long-tail keywords are specific, lower-volume search terms. Each brings little traffic, but together they’re easier to rank for and often convert well.
Looker Studio
Looker Studio, renamed Data Studio in 2026, is Google’s free dashboard tool, often used to build SEO reports from Search Console and GA4.
Lost backlinks
Lost backlinks are links that used to point to your site but no longer do, because the link, page or target URL changed or was removed.
LSI keywords
LSI keywords is an SEO name for related terms. Google says it doesn’t use latent semantic indexing; what matters is covering the topic’s related concepts.

M

Manual action (Google penalty)
A manual action is a penalty a Google reviewer applies when a site breaks its spam policies, demoting or removing pages until the issue is fixed.
Meta description
A meta description is an HTML tag that summarises a page. Google may show it as the snippet under the title; it affects clicks, not rankings.
Meta keywords tag
The meta keywords tag is an old HTML tag for listing a page’s keywords. Google ignores it for ranking and has done since at least 2009.
Meta robots tag
A meta robots tag is an HTML tag that tells search engines whether to index a page, follow its links and how to show it in results.
Mixed content
Mixed content is when an HTTPS page loads images, scripts or other files over insecure HTTP. Browsers block or upgrade much of it.
Mobile-first indexing
Mobile-first indexing means Google crawls and indexes the mobile version of your pages and uses it for ranking, on mobile and desktop alike.
Model Context Protocol (MCP)
Model Context Protocol (MCP) is an open standard that lets AI assistants connect to outside tools and data, such as an SEO platform’s API.

N

NAP (name, address, phone)
NAP stands for name, address and phone number. Keeping your NAP consistent across your site, profiles and directories supports local SEO.
Navigational intent
Navigational intent is when a searcher wants to reach a specific website or page, such as "gmail login" or "ikea returns".
"Near me" searches
“Near me” searches are queries such as “pharmacy near me”, where Google uses the searcher’s location to show nearby businesses.
Negative SEOBlack hat
Negative SEO is the use of black hat tactics against someone else’s site, such as spammy links, hacking or fake reviews, to hurt its rankings.
Niche edits (link insertions)Grey hat
A niche edit adds a link to an existing article on another site. Asking for a useful update is fine; paying for the insertion makes it a paid link.
Nofollow
Nofollow is a link attribute or meta directive asking search engines not to follow or credit links. Google treats it as a hint.
Nofollow link
A nofollow link carries rel="nofollow", asking search engines not to pass ranking credit. Since 2019 Google treats it as a hint, not a rule.
Noindex
Noindex is a robots directive, set in a meta tag or HTTP header, that tells search engines not to show a page in search results.

O

Off-page SEO
Off-page SEO is everything done outside your own site to build its reputation and rankings, mainly earning backlinks, mentions and reviews.
On-page SEO
On-page SEO is optimising the content and HTML of each page, such as text, title tag, headings, images and internal links, to rank and earn clicks.
On-page SEO checklist
An on-page SEO checklist is a list of items to check on each page, from intent and title tag to headings, images, links and structured data.
Online reviews
Online reviews are customer ratings and comments on platforms such as Google, Yelp and Trustpilot. They shape local rankings and buying decisions.
Open Graph tags
Open Graph tags are meta tags that control how a page looks when shared on social platforms and messaging apps: title, description and image.
Organic CTR by position
Organic CTR by position is the pattern of how click-through rate falls as a result moves down the page: top results get most clicks.
Organic search
Organic search is the unpaid part of search results, where pages appear because the search engine judged them relevant, not because someone paid.
Organic traffic
Organic traffic is the visitors who reach your site by clicking an unpaid search result rather than an ad, link or social post.
Orphan page
An orphan page is a page with no internal links pointing to it, so visitors and crawlers cannot reach it by browsing the site.
Outbound links
Outbound links are links from your site to other websites. Linking to useful sources helps readers and does not drain your rankings.

P

Page speed
Page speed is how quickly a page loads, shows its content and responds to input. Google measures it mainly through Core Web Vitals.
PageRank
PageRank is Google’s original algorithm for scoring pages by the number and quality of links pointing to them. Google still uses a version of it.
PageSpeed Insights
PageSpeed Insights is Google’s free tool that shows a page’s real-user Core Web Vitals and a Lighthouse lab test with suggestions, for mobile and desktop.
Pagination
Pagination splits a long list of items, such as products or articles, across a series of numbered pages, each with its own URL.
Paid linksBlack hat
Paid links are links bought to pass ranking credit, without rel="sponsored" or nofollow, which breaks Google’s link spam policy.
Paid search results
Paid search results are ads shown on search results pages, labelled Sponsored on Google, where advertisers pay when someone clicks.
Parent topic
A parent topic is the broader keyword that the top-ranking page for a search gets most of its traffic from. It shows whether one page can cover both.
People Also Ask
People Also Ask is a Google results box of questions related to the search. Each one expands to show a short answer from a web page, with a link.
Perplexity
Perplexity is an AI answer engine that searches the web for each question and writes an answer with numbered citations to its sources.
Pillar page
A pillar page is a broad, in-depth page on a core topic that links to more detailed pages on each subtopic, forming the hub of a topic cluster.
Position zero
Position zero is the informal name for a featured snippet: the answer box Google shows above the first standard organic result.
Primary keyword
A primary keyword is the main search term a page is built to rank for. It guides the page’s title, H1, URL and content.
Private blog network (PBN)Black hat
A private blog network (PBN) is a group of sites, often on expired domains, built only to link to a money site and boost its rankings.
Programmatic SEO
Programmatic SEO is creating many pages from templates and data to target large sets of similar searches, such as “X in [city]” queries.
Prompt tracking
Prompt tracking is running a fixed set of questions through AI assistants on a schedule to track brand mentions, citations and position.

Q

Query fan-out
Query fan-out is when an AI search system splits one question into many related searches, runs them together and combines the results.
Question keywords
Question keywords are searches phrased as questions, like "how do solar panels work". They often trigger featured snippets and People Also Ask.

R

Rank tracking
Rank tracking is checking where your pages rank in search results for chosen keywords over time, by device and location, to measure SEO progress.
Ranking distribution
Ranking distribution shows how many of a site’s keywords sit in each position band, such as 1–3, 4–10, 11–20 and 21–100.
Ranking factors
Ranking factors are the signals search engines use to decide how high a page appears, such as relevance, content quality, links and page experience.
Readability
Readability is how easy a text is to read and understand, shaped by sentence length, word choice, structure and layout.
Reciprocal linksGrey hat
Reciprocal links are when two sites link to each other. Natural ones are normal; excessive or arranged swaps for rankings are a link scheme.
Reconsideration request
A reconsideration request asks Google to review a site after you fix the issue behind a manual action, so the action can be lifted.
Redirect chain
A redirect chain is when a URL redirects to another URL that redirects again, so it takes two or more hops to reach the final page.
Redirect loop
A redirect loop is when redirects send a URL back to itself, so the page never loads and browsers show a too-many-redirects error.
Referring domain
A referring domain is a website that links to your site at least once. Each domain counts once, no matter how many links it sends.
Related searches
Related searches are the query suggestions Google shows on the results page, often at the bottom, to help people refine or broaden their search.
Render-blocking resources
Render-blocking resources are CSS and JavaScript files that the browser must download and process before it can show any of the page.
Rendering
Rendering is when a search engine runs a page’s HTML, CSS and JavaScript to build the page as a browser would, so it can see the final content.
Retrieval-augmented generation (RAG)
Retrieval-augmented generation (RAG) is when an AI system fetches relevant documents first and then writes its answer from them.
Review gatingBlack hat
Review gating is asking customers how they feel first and only sending happy ones to leave public reviews. It breaks Google’s review policies.
Review response rate
Review response rate is the share of customer reviews a business has replied to. Replies show customers you listen and help manage your reputation.
Rich results
Rich results are Google search results with extra visual features, such as star ratings, prices or event dates, usually powered by structured data.
Rich snippets
Rich snippets are search results enhanced with extra details, such as review stars, prices or cooking times, usually from structured data.
Robots.txt
Robots.txt is a plain-text file at the root of a site that tells crawlers which URLs they may and may not request.

S

Scaled content abuseBlack hat
Scaled content abuse is producing many pages mainly to manipulate rankings, with little value for users, whether made by AI, people or both.
Schema markup
Schema markup is structured data that uses the schema.org vocabulary to describe things on a page, such as products, articles and businesses.
Scraped contentBlack hat
Scraped content is material copied from other sites and republished, with little or no change or added value, against Google’s scraping policy.
Search algorithm
A search algorithm is the set of systems a search engine uses to decide which indexed pages to show for a query and in what order.
Search Console Performance report
The Search Console Performance report shows clicks, impressions, CTR and average position for your site in Google Search, by query, page and more.
Search engine
A search engine is a system that finds pages on the web, stores them in an index and returns the most relevant ones for each query.
Search engine marketing (SEM)
Search engine marketing (SEM) is promoting a website in search engines. It usually means paid search ads, and sometimes means SEO plus ads together.
Search intent
Search intent is the reason behind a search: what the person wants to know, find or do. Matching it is one of the most important parts of SEO.
Search Quality Rater Guidelines
The Search Quality Rater Guidelines are Google’s public handbook for human raters who assess the quality of search results.
Search volume
Search volume is the estimated number of times a keyword is searched per month in a given location, usually averaged over the past 12 months.
Secondary keywords
Secondary keywords are related terms a page targets alongside its primary keyword: variations, synonyms and subtopics with the same intent.
Security headers
Security headers are HTTP response headers that tell browsers how to handle a site’s content safely, blocking common attacks.
Seed keyword
A seed keyword is a short starting term, like "coffee" or "CRM", that you expand into a longer list of keyword ideas during keyword research.
Semantic search
Semantic search is search that matches the meaning and intent behind a query, not just its exact words.
SEO (search engine optimization)
SEO (search engine optimization) is the work of making your website easier to find, understand and choose in unpaid search results.
SEO audit
An SEO audit is a review of a website’s technical health, content and links to find what holds it back in search and what to fix first.
SEO copywriting
SEO copywriting is writing web copy that ranks in search and persuades readers, by matching search intent and answering clearly.
SEO KPIs
SEO KPIs are the metrics you choose to judge whether SEO is working, such as organic clicks, rankings, visibility and key events from organic search.
SEO reporting
SEO reporting is the regular summary of search performance, explaining what changed, why, and what to do next, for a team or client.
SEO ROI
SEO ROI is the return from organic search compared with what you spent on it: (value from SEO − cost of SEO) ÷ cost of SEO.
SEO strategy
An SEO strategy is a plan for which searches to win, which pages to create or improve, and how to earn the authority to rank for them.
SEO visibility score
An SEO visibility score is a single number showing how visible a site is in search for a set of keywords, weighting rankings by expected clicks.
SEO-friendly URL
An SEO-friendly URL is short, readable and descriptive, uses hyphens and lowercase, and shows where a page sits in the site’s structure.
SERP (search engine results page)
A SERP (search engine results page) is the page a search engine shows after a query: organic links, ads, and features like snippets and maps.
SERP features
SERP features are the results on Google’s results page that are not plain blue links, such as AI Overviews, featured snippets, local packs and videos.
SERP volatility
SERP volatility is how much search results change over a period. High volatility often signals a Google update or a shake-up in a niche.
Server-side rendering (SSR)
Server-side rendering (SSR) builds a page’s full HTML on the server for each request, so browsers and crawlers get the content in the first response.
Service area business
A service area business visits or delivers to customers rather than serving them at its address, such as a plumber, cleaner or mobile mechanic.
Share of voice
Share of voice is your share of the visibility in a market, such as the share of AI answers or search clicks that go to you versus competitors.
Shopping results
Shopping results are product listings in Google Search showing images, prices and stores, from Merchant Center feeds or product structured data.
Site architecture
Site architecture is how a website’s pages are organised and linked together, which shapes how people and search engines find and value them.
Site health score
A site health score is a single number, usually 0 to 100, that an SEO audit tool calculates from the technical issues found when it crawls a site.
Site reputation abuse (parasite SEO)Black hat
Site reputation abuse, or parasite SEO, is publishing third-party pages on a trusted site mainly to borrow its ranking power, against Google’s policies.
Sitelinks
Sitelinks are extra links to other pages of a site that Google shows under a search result, usually for brand searches.
Skyscraper techniqueWhite hat
The skyscraper technique means finding content that earned many links, making something clearly better, and asking the linking sites to cite yours.
Sneaky redirectsBlack hat
Sneaky redirects send users to a different page than the one search engines saw, to deceive them, which breaks Google’s spam policies.
Soft 404
A soft 404 is a page that returns a 200 success code but looks like an error or empty page, so Google treats it as not found.
SpamBrain
SpamBrain is Google’s AI-based spam prevention system, used to detect spam content and link spam in search results.
rel="sponsored"
rel="sponsored" is a link attribute that marks a link as paid, sponsored or an affiliate link, so it does not pass ranking credit.
Striking distance keywords
Striking distance keywords are queries a page ranks for just off the top spots, roughly positions 5-20, where small improvements can bring big gains.
Structured data
Structured data is code in a standard format that describes a page’s content to search engines, making it eligible for rich results.
Structured data spamBlack hat
Structured data spam is schema markup that misleads, such as fake review stars or markup for content not on the page, to win rich results.

T

Technical SEO
Technical SEO is making sure search engines can crawl, render and index your site, covering speed, redirects, canonicals, sitemaps and mobile.
Thin affiliate pagesBlack hat
Thin affiliate pages are affiliate pages that copy product descriptions or reviews from the merchant and add no original value, against Google’s policy.
Thin content
Thin content is a page with little or no useful content of its own, such as near-empty pages, copied text or doorway pages.
Time to First Byte (TTFB)
Time to First Byte (TTFB) is the time from requesting a page until the first byte of the response arrives. It sets the floor for every other speed metric.
Title tag
A title tag is the HTML element that names a page. Google often uses it as the clickable headline in results, so it affects rankings and clicks.
Title tag length
Title tag length is how long a page title is. Google truncates by pixel width, about 600px on desktop, so aim for roughly 50 to 60 characters.
Top stories
Top stories is the Google results section that shows recent news articles about a query, usually as a carousel or list near the top.
Topic cluster
A topic cluster is a group of pages about one subject: a pillar page covering it broadly, linked to cluster pages that cover subtopics in depth.
Topical authority
Topical authority is a site’s perceived depth and expertise on a subject, built by covering it thoroughly and being cited on it.
Toxic backlinks
Toxic backlinks are low-quality or manipulative links to your site. Google ignores most of them; only links from schemes you built tend to need action.
Traffic potential
Traffic potential estimates the total organic traffic you could get by ranking first for a topic, counting every related query the top page ranks for.
Traffic value
Traffic value estimates what a site’s organic traffic would cost if you bought the same clicks with search ads, using each keyword’s CPC.
Transactional intent
Transactional intent is when a searcher is ready to act: buy, book, sign up or download, with searches like "buy", "price" or "order".
Twitter card (X card)
A Twitter card (now X card) is a set of meta tags that controls how a link looks when posted on X, including its title, description and image.

U

rel="ugc"
rel="ugc" is a link attribute for links inside user-generated content, such as comments and forum posts, signalling the site does not vouch for them.
Unlinked brand mentionsWhite hat
Unlinked brand mentions are places that name your brand, product or people without linking to you. Asking for a link is an easy white hat win.
URL parameters
URL parameters are key-value pairs after a ? in a URL, used for tracking, sorting, filtering and pagination. Each variation can look like a new page.
URL Rating (UR)
URL Rating (UR) is Ahrefs’ 0–100 score of the strength of one page’s backlink profile, including internal and external links.
URL slug
A URL slug is the last part of a URL that names a specific page, such as /blue-running-shoes. Short, readable slugs help users and search engines.
User agent
A user agent is the software making a web request, identified by a user-agent string such as Googlebot’s that servers and robots.txt can read.
User-generated content
User-generated content (UGC) is content created by a site’s users rather than its owners, such as reviews, comments, forum posts and Q&A.
UTM parameters
UTM parameters are tags added to a URL, such as utm_source and utm_medium, that tell analytics tools where a visit came from.

V

Video carousel
A video carousel is a scrollable row of video results in Google Search, often from YouTube, shown when video suits the query.
Viewport meta tag
The viewport meta tag tells mobile browsers how to size and scale a page. Without it, phones show a shrunken desktop layout.

W

Web crawler
A web crawler is an automated program that visits web pages, downloads them and follows their links, used by search engines and SEO tools.
White hat SEOWhite hat
White hat SEO is search optimisation that follows Google’s guidelines: useful content, a crawlable site and links you earn rather than buy.
White hat vs grey hat vs black hat SEO
White hat SEO follows Google’s rules, black hat SEO breaks its spam policies, and grey hat SEO sits in between, where tactics can tip into spam.
Word count
Word count is the number of words on a page. Google says it isn’t a ranking factor; the right length is whatever fully answers the query.

X

X-Robots-Tag
X-Robots-Tag is an HTTP response header that gives search engines robots directives such as noindex, including for PDFs and images.
XML sitemap
An XML sitemap is a file that lists the URLs you want search engines to crawl and index, with optional last-modified dates.

Y

YMYL (Your Money or Your Life)
YMYL (Your Money or Your Life) means topics that could affect someone’s health, finances, safety or wellbeing, where Google applies higher standards.

Z

Zero-click searches
Zero-click searches are searches that end without a click to any website, because the answer is on the results page or the user gives up.
Zero-volume keywords
Zero-volume keywords are searches that keyword tools report as having no monthly volume, though many still get real searches and clicks.

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