Plain-English definitions
The terminology buyers and AI assistants both reach for. Schema-marked, citation-ready.
SEO (Search Engine Optimisation)
The discipline of making a site rank for queries buyers actually type.
AEO (Answer Engine Optimisation)
The discipline of formatting content so AI assistants will cite it.
GEO (Generative Engine Optimisation)
AEO's narrower cousin, focused specifically on generative answer engines.
Programmatic SEO
Generating SEO pages from a structured entity registry rather than authoring each by hand.
Schema.org markup
Structured-data vocabulary that tells search engines and assistants what a page is about.
JSON-LD
JSON-formatted Linked Data — the recommended way to embed schema.org markup.
Core Web Vitals
Google's UX performance metrics: LCP, INP, CLS.
LCP (Largest Contentful Paint)
Time until the largest visible element finishes rendering.
INP (Interaction to Next Paint)
Time until the page paints in response to a user interaction.
CLS (Cumulative Layout Shift)
Sum of all unexpected layout shifts during a page's life.
hreflang
HTML attribute or HTTP header that tells search engines the language/region of a page.
llms.txt
Emerging convention for declaring a site's purpose and key URLs to AI crawlers.
Thin content
Pages with insufficient unique value to justify indexing.
Internal link graph
The structure of links between pages on the same site.
Hub-and-spoke architecture
Content structure where one authoritative hub page links to many specific spoke pages, all linking back.
i18n (Internationalisation)
Software design for multi-language/region deployment without code changes per locale.
Locale
A combination of language + region (e.g. en-GB, en-US, en-AU).
Canonical URL
The preferred URL for a piece of content when multiple URLs serve the same content.
IndexNow
Protocol for instantly notifying search engines (Bing, Yandex) of new or updated URLs.
XML sitemap
Machine-readable list of URLs on a site, used by search engines for crawl discovery.
TTFB (Time to First Byte)
Time from request to first byte of response. Server-side speed indicator.
Rich results
Enhanced SERP listings powered by structured data (stars, prices, FAQs, etc.).
Featured snippet
Answer block at the top of SERP, pulled from a single ranking page.
Knowledge panel
Right-side SERP card with entity information (companies, people, places).
E-E-A-T
Experience, Expertise, Authoritativeness, Trustworthiness — Google's quality framework.
YMYL (Your Money, Your Life)
Topics affecting financial stability, health, safety, civic life.
Topical authority
Site's perceived expertise in a defined topic, signalled by depth + breadth of content.
Crawl budget
Volume of URLs Googlebot will crawl on a site in a given period.
Noindex
Meta tag instructing search engines not to include a page in the index.
robots.txt
Text file at site root that gives crawl directives to user-agents.
Redirect chain
Multiple redirects between an original URL and the final destination.
Link equity (PageRank)
Authority that flows through hyperlinks from one URL to another.
Nofollow
Link attribute instructing search engines not to pass equity through this link.
Anchor text
Visible, clickable text of a hyperlink.
Topic cluster
Hub page plus 5–15 related spoke pages covering sub-topics.
Search intent
What the user is trying to accomplish with their query.
SERP
Search Engine Results Page.
CTR (Click-Through Rate)
Proportion of impressions that result in a click.
Impressions
Number of times a URL appeared in SERPs.
Google Search Console
Free first-party tool for SEO performance + indexing data from Google.
CrUX (Chrome User Experience Report)
Public dataset of real-user Chrome performance data per origin.
Field data
Real-user performance measurements (vs lab data from synthetic tests).
Lab data
Synthetic performance measurements from controlled test environments.
Structured data
Machine-readable data embedded in pages (JSON-LD, microdata, RDFa).
Open Graph (OG)
Meta-tag protocol for rich link previews on Facebook, LinkedIn, Slack, etc.
Meta tags
HTML head tags that describe page metadata.
SSG (Static Site Generation)
Rendering strategy that pre-renders pages at build time.
SSR (Server-Side Rendering)
Rendering strategy that produces HTML on each request.
ISR (Incremental Static Regeneration)
Hybrid rendering: serve cached static pages, regenerate in background after TTL.
Lighthouse
Google's open-source page-quality auditing tool.
PageSpeed Insights
Google tool combining Lighthouse (lab) + CrUX (field) data.
JavaScript SEO
Techniques for ensuring JavaScript-rendered content indexes correctly.