SEO terms, defined. Know what each one means. Know what to check on your site.

A 301 redirect permanently sends users and search engines from one URL to another, and passes ranking signals to the destination.

A 302 redirect temporarily sends users to another URL while signaling that the original should remain the indexed version.

A 404 error is the status code returned when a requested page does not exist.

AI crawlers are bots that collect web content for AI companies, either to train models or to retrieve pages in real time for answers.

AI Mode is Google's conversational search experience that answers complex questions with AI-generated responses and follow-up questions, citing web sources.

AI Overviews are AI-generated summaries Google shows at the top of some search results, with links to the sources used.

AI search visibility describes how often a brand or website appears, is mentioned, or is cited across AI-generated search answers.

An algorithm update is a change to how a search engine ranks results.

Alt text is a text description of an image in the HTML alt attribute.

Anchor text is the clickable text of a link.

Answer Engine Optimization is the practice of structuring content so it can be selected as a direct answer by featured snippets, voice assistants, and AI systems.

Authority metrics such as Domain Authority (Moz) and Domain Rating (Ahrefs) are third-party scores estimating a site's link strength.

Average position in Search Console is the mean ranking of your highest result across all impressions for a query or page.

A backlink is a link from another website to yours.

A baseline is a recorded snapshot of normal performance, such as rankings, indexed pages, or traffic, used to compare future changes against.

Black hat SEO refers to tactics that violate search engine spam policies to manipulate rankings, such as cloaking, keyword stuffing, and buying links.

Bounce rate traditionally meant the share of single-page sessions.

Brand mentions in AI answers are references to your brand in AI-generated responses, with or without a link.

A branded keyword is a query that includes a brand name, such as "SiteAuditLint pricing." Non-branded keywords do not mention a brand.

A breadcrumb is a navigation trail showing a page's position in the site hierarchy, such as Home > Academy > SEO Terms.

A canonical tag is an HTML link element that tells search engines which URL is the preferred version when several URLs show the same or very similar content.

Canonicalization is the process by which a search engine chooses one representative URL from a group of duplicate or near-duplicate pages.

Change detection is automatically identifying changes to SEO-critical page elements, such as titles, canonicals, robots directives, or content.

A citation in AI search is a linked source an AI answer references, usually shown inline or in a sources list.

Click-through rate is the percentage of impressions that result in a click, calculated as clicks divided by impressions.

In Search Console, a click is counted when a user clicks a search result that leads to your site.

Client-side rendering builds page content in the browser with JavaScript after the initial HTML loads.

A content cluster is a group of interlinked pages covering a topic in depth, typically organized around a pillar page.

Content decay is the gradual decline in a page's traffic and rankings over time, often because content becomes outdated or competitors publish better pages.

Content pruning is removing, merging, or noindexing low-value pages to improve a site's overall quality and focus.

A conversion is a valuable action a visitor completes, such as a signup, purchase, or demo request.

A core update is a significant, broad change to Google's ranking systems, announced several times a year.

Core Web Vitals are three Google metrics measuring real-user page experience: Largest Contentful Paint for loading, Interaction to Next Paint for responsiveness, and Cumulative Layout Shift for visual stability.

Crawl budget is the number of URLs a search engine can and wants to crawl on a site within a given time.

Crawl depth is the number of clicks needed to reach a page from the homepage.

A crawl trap is a site structure that generates a near-infinite number of URLs, such as endless calendar pages or combinable filters, wasting crawl resources.

A crawler, also called a bot or spider, is a program that search engines use to fetch web pages and follow their links.

Crawling is the process by which search engines discover and fetch URLs, usually by following links and reading XML sitemaps.

Cumulative Layout Shift measures how much visible content moves unexpectedly while a page loads.

Deployment checks are the combined set of pre-deployment and post-deployment SEO tests built into a release process.

Disavowing is telling Google, through the Disavow links tool, to ignore specific backlinks to your site.

Dofollow is an informal term for a normal link without a nofollow, sponsored, or ugc attribute.

Duplicate content is identical or very similar content appearing at more than one URL, on the same site or across sites.

Duplicate URL clustering is how search engines group URLs with the same content before choosing a canonical, for example versions with tracking parameters or different capitalization.

Dynamic rendering serves pre-rendered HTML to bots and client-side rendered pages to users.

E-E-A-T stands for Experience, Expertise, Authoritativeness, and Trustworthiness.

Edge SEO is making SEO changes at the CDN or edge level, such as redirects, headers, or HTML edits, without changing the origin codebase.

An entity is a distinct, well-defined thing, such as a person, organization, place, product, or concept, that search engines can identify and relate to other entities.

Evergreen content stays relevant and useful for a long time, such as definitions, guides, and how-tos, as opposed to news.

Faceted navigation lets users filter listings by attributes such as size, color, or price, often creating many URL combinations.

A featured snippet is a highlighted answer shown near the top of the SERP, extracted from a web page.

Generative Engine Optimization is the practice of improving how often and how accurately a brand or page is cited in AI-generated answers.

Google Business Profile is Google's free listing tool for local businesses, controlling how a business appears in Maps and the local pack.

Google Search Console is Google's free tool for monitoring how a site performs in Google Search, including queries, indexing, and technical issues.

Google-Extended is a robots.txt token that lets sites control whether their content is used to train and ground Google's Gemini models.

Googlebot is Google's web crawler, with smartphone and desktop variants.

GPTBot is OpenAI's crawler for collecting content that may be used to train its models.

Grounding is connecting an AI model's response to verifiable source information, such as search results or documents, to improve accuracy.

A head term is a short, broad, high-volume keyword, such as "SEO" or "running shoes." Head terms are usually competitive and have mixed intent.

Heading tags structure a page's content hierarchy, from the H1 main heading down through H2 to H6 subheadings.

The helpful content system was a Google ranking system designed to reward content created for people rather than search engines.

Historical comparison is comparing current SEO data with earlier periods to identify trends, regressions, and seasonality.

Hreflang is an attribute that tells search engines which language or regional version of a page to show to which users.

Hreflang return tags are the reciprocal references required between alternate pages.

HTTPS is the secure version of HTTP, encrypting data between the browser and the server.

Image optimization is reducing image file size and improving image delivery and context so pages load fast and images can rank in image search.

An impression is counted when a link to your site appears in search results a user sees, whether or not they scroll to it or click.

Index bloat happens when a site has many low-value pages indexed, such as filter pages, tag archives, or internal search results.

Indexability is whether a page is eligible to be indexed.

Indexing is the process of analyzing a crawled page and storing it in the search engine's index, the database that results are drawn from.

Information gain describes how much new, useful information a page adds beyond what other pages on the same topic already provide.

Interaction to Next Paint measures how quickly a page responds visually to user interactions such as clicks and taps.

An internal link is a hyperlink from one page to another page on the same website.

JavaScript SEO is the practice of making JavaScript-heavy sites crawlable, renderable, and indexable by search engines.

A keyword is a word or phrase that people type or speak into a search engine.

Keyword cannibalization happens when several pages on the same site target the same query and intent, so they compete and none ranks as well as one strong page would.

Keyword clustering is grouping keywords that share the same intent and SERP results so they can be targeted by one page.

Keyword difficulty is a third-party score estimating how hard it is to rank for a keyword, usually based on the backlinks of current top results.

Keyword research is the process of finding the queries your audience searches for and judging their volume, intent, difficulty, and business value.

The Knowledge Graph is Google's database of entities and the relationships between them, used to power knowledge panels and understand queries.

A knowledge panel is an information box Google shows for entities such as people, organizations, and places, drawn largely from the Knowledge Graph.

A landing page is the page a visitor first arrives on, whether from search, ads, or another source.

A large language model is an AI system trained on large amounts of text to understand and generate language.

Largest Contentful Paint measures how long the largest visible element, often a hero image or heading, takes to render.

Link building is the practice of earning links from other websites, for example through original research, digital PR, or useful tools.

Link equity, often called link juice, is the ranking value passed from one page to another through links.

LLM visibility is how a brand is represented in responses from large language models, including both mentions from training data and citations retrieved from the web.

llms.txt is a proposed standard file at a site's root that gives AI models a curated, plain-text summary of a site's key content.

The local pack is the map and set of business listings Google shows for queries with local intent.

Local SEO is optimizing a business's online presence to appear in location-based searches, such as "dentist near me" and Google Maps results.

Log file analysis is reviewing server logs to see exactly which URLs search engine and AI crawlers request, how often, and what status codes they receive.

A long-tail keyword is a more specific, lower-volume query, often three or more words long, such as "how to fix redirect chains in WordPress."

A manual action is a penalty applied by a human reviewer at Google when a site violates spam policies.

A meta description is an HTML element summarizing a page's content.

A meta robots tag is an HTML element in the page head that gives search engines page-level directives, such as noindex or nofollow.

Mobile-first indexing means Google primarily uses the mobile version of a page's content for indexing and ranking.

A mobile-friendly page is easy to read and use on a smartphone, with readable text, tappable buttons, and no horizontal scrolling.

NAP consistency means a business's Name, Address, and Phone number appear identically across the web.

Nofollow is a link attribute (rel="nofollow") telling search engines not to associate the linking page with the target.

Noindex is a directive telling search engines not to include a page in their index.

Off-page SEO covers actions outside your website that influence rankings, mainly earning backlinks, brand mentions, and reviews.

On-page SEO is optimizing elements on the page itself, such as content, title tags, headings, and internal links, to improve relevance and usability.

Organic traffic is visits that come from unpaid search results.

Organic search results are earned through relevance and quality, while paid search results are ads bought through platforms like Google Ads.

An orphan page is a page with no internal links pointing to it, making it hard for users and crawlers to find.

The Page indexing report in Search Console shows which of your URLs are indexed and why others are not, such as noindex, redirects, or duplicates.

Page speed describes how quickly a page loads and becomes usable.

PageRank is Google's original algorithm for measuring a page's importance based on the quantity and quality of links pointing to it.

Pagination splits content across numbered pages, such as category pages 1, 2, and 3.

Parameter handling is how a site manages URL parameters for tracking, sorting, and filtering so they do not create duplicate or wasteful URLs.

Passage ranking is Google's ability to rank a specific section of a long page for a query, even when the page as a whole covers a broader topic.

People Also Ask, or PAA, is a SERP feature showing expandable related questions, each with a short answer pulled from a web page.

A pillar page is a comprehensive page covering a broad topic that links out to more detailed pages on related subtopics.

A post-deployment check is an SEO review run on the live site immediately after a release, to confirm nothing broke in production.

A pre-deployment check is an SEO review run on staging before a release, to catch issues before they reach the live site.

Programmatic SEO is creating many pages at scale from templates and structured data, such as location or comparison pages.

Query fan-out is a technique where an AI search system breaks one question into several related sub-queries, searches them in parallel, and combines the results.

Rank tracking is monitoring where your pages rank for a defined set of keywords over time, by location and device.

Ranking is the position a page holds in search results for a given query.

A ranking factor is any signal a search engine uses to decide the order of results, such as relevance, content quality, links, and page experience.

Ranking volatility is how much search rankings fluctuate over a period, across your site or across the whole SERP.

A redirect chain occurs when a URL redirects to another URL that redirects again before reaching the final destination.

A redirect loop occurs when URLs redirect to each other in a cycle, so the page never loads.

Regression testing is re-testing existing functionality after a change to make sure nothing that previously worked has broken.

Rendering is the process of executing a page's HTML, CSS, and JavaScript to produce the final page that users and search engines see.

Retrieval-augmented generation is a method where an AI system retrieves relevant documents first, then uses them to generate its answer.

Rich results are enhanced search listings that show extra information, such as review stars, product prices, or event dates, usually enabled by structured data.

Robots.txt is a text file at the root of a domain that tells crawlers which paths they may or may not crawl.

Schema markup is structured data using the Schema.org vocabulary, such as Article, Product, Organization, or BreadcrumbList.

A search engine is a system that discovers, stores, and ranks web content so it can return relevant results for a user's query.

Search intent is the goal behind a query.

Search volume is the estimated number of times a keyword is searched in a given period, usually per month.

A self-referencing canonical is a canonical tag that points to the page's own URL, confirming it as the preferred version.

Semantic search is a search engine's ability to understand the meaning and context of a query, not just match its exact words.

SEO alerting is sending automatic notifications when monitored metrics cross defined thresholds, such as a spike in 5xx errors or a removed canonical.

An SEO audit is a structured review of a site's technical health, content, and links to find issues limiting search performance.

SEO evidence is the documented data proving an SEO issue, fix, or impact, such as crawl results, screenshots, logs, and before-and-after comparisons.

SEO monitoring is the ongoing tracking of rankings, traffic, indexing, and technical health to catch problems early.

An SEO regression is a change that unintentionally harms search performance, such as a lost canonical, an accidental noindex, or broken internal links.

A SERP, or search engine results page, is the page a search engine shows in response to a query.

Server-side rendering generates the full HTML on the server before sending it to the browser, so content is visible without running JavaScript first.

Share of voice in SEO is the percentage of total available search visibility your site captures for a defined keyword set, compared with competitors.

A site migration is any major change to a site's URLs, domain, platform, or structure that can affect search visibility.

A slug is the part of a URL that identifies a specific page, such as on-page-seo in /academy/seo-terms/on-page-seo.

A soft 404 is a page that tells users it does not exist, or has almost no content, but returns a 200 status code instead of 404.

Spam policies are Google's published rules describing manipulative practices that can lead to lower rankings or removal from results, such as scaled content abuse and link spam.

A staging environment is a non-public copy of a site used to test changes before they go live.

HTTP status codes are three-digit responses a server returns for each request, telling browsers and crawlers whether a URL succeeded (2xx), redirected (3xx), was not found (4xx), or failed (5xx).

Structured data is code in a standardized format, usually JSON-LD, that describes a page's content to search engines in a machine-readable way.

Technical SEO validation is confirming that technical SEO requirements are correctly implemented, such as redirects, canonicals, hreflang, and structured data.

Thin content is a page with little original value for users, such as near-empty pages, auto-generated text, or doorway pages.

Time to First Byte is the time between a browser requesting a page and receiving the first byte of the response.

A title tag is the HTML element that defines a page's title, often shown as the clickable headline in search results.

Topical authority describes a site's perceived depth and expertise on a subject, built by covering the topic thoroughly and accurately over time.

An unlinked mention is a reference to your brand, product, or content on another site that does not include a link.

A URL is the web address of a page.

User experience is how easy and satisfying a page is to use, including layout, readability, speed, and navigation.

A visibility index is a single score estimating how visible a site is in search for a keyword set, weighting rankings by position and search volume.

White hat SEO refers to optimization practices that follow search engine guidelines and focus on users, such as creating helpful content and improving site quality.

The X-Robots-Tag is an HTTP header that carries robots directives, such as noindex, for any file type, including PDFs and images.

An XML sitemap is a file listing the URLs you want search engines to discover and crawl, optionally with last-modified dates.

A zero-click search is a search where the user gets their answer on the SERP and does not click any result.