SEO Glossary

A

Above the fold — Content visible without scrolling on initial page load. Critical for LCP.

Alt text — Description of an image for screen readers and image search. Required on all content images.

Anchor text — The clickable text in a hyperlink. Strong on-page SEO signal.

Anonymized queries — Search Console hides query data for very low-volume searches (privacy protection).

B

Backlink — A link from another site to yours. Major ranking factor.

BERT — Google’s language model used in search query understanding (since 2019).

Breadcrumb — Navigation showing the page’s location in site hierarchy. Often marked up with BreadcrumbList JSON-LD.

C

Canonical URL — The authoritative version of a piece of content, declared via <link rel="canonical">.

CCBot — Common Crawl’s bot, used to train AI models. Blockable via robots.txt.

CLS (Cumulative Layout Shift) — Core Web Vital measuring visual stability. <0.1 is “Good”.

Core Web Vitals — Google’s three performance metrics: LCP, INP, CLS.

Crawl budget — Number of URLs Googlebot crawls on your site per day.

Crawler (or bot) — Automated agent that reads web pages (Googlebot, Bingbot, etc.)

CSP (Content Security Policy) — HTTP header restricting which scripts/resources can load. Indirectly affects SEO.

CTR (Click-Through Rate) — Clicks ÷ impressions in search results.

D

DNS (Domain Name System) — Maps domain names to IP addresses.

Disavow — Telling Google to ignore specific backlinks. Used for toxic links.

Domain authority — Third-party metric estimating SEO strength. NOT a Google ranking factor (just an estimate by tools like Moz/Ahrefs).

E

E-E-A-T (Experience, Expertise, Authoritativeness, Trustworthiness) — Google’s content quality framework, especially important for YMYL topics.

EXIF data — Metadata embedded in image files (GPS, camera). Strip on upload.

F

Featured snippet — Highlighted answer box at the top of search results. Often the “position 0”.

FID (First Input Delay) — Old responsiveness metric, replaced by INP in March 2024.

FOIT (Flash of Invisible Text) — Text temporarily invisible while custom font loads. Avoid with font-display: swap.

FOUT (Flash of Unstyled Text) — Text shown in fallback font, then swapped to custom. Better than FOIT for users.

G

Googlebot — Google’s web crawler.

GSC (Google Search Console) — Google’s webmaster tool. Free.

H

Hreflang — HTML annotation indicating language/region targeting.

HSTS (HTTP Strict Transport Security) — Header forcing HTTPS.

HTTP status code — Server response code (200, 301, 404, etc.). See HTTP Status Codes Reference.

I

Impressions — Number of times your URL appeared in search results (whether clicked or not).

Indexable — A page that crawlers can access AND that has no noindex directive.

IndexNow — Protocol for instantly notifying Bing/Yandex of URL changes. See IndexNow guide.

Indexing — When a search engine adds your page to its database. Different from crawling.

INP (Interaction to Next Paint) — Core Web Vital replacing FID in March 2024. Measures responsiveness. <200ms is “Good”.

ISR (Incremental Static Regeneration) — Static generation with auto-refresh after a defined interval.

J

JSON-LD (JavaScript Object Notation for Linked Data) — Google’s preferred format for structured data.

K

Keyword — Word or phrase a user searches. (Not to be confused with the deprecated <meta name="keywords"> tag.)

Knowledge Graph — Google’s database of entities (people, places, organizations) and their relationships.

L

LCP (Largest Contentful Paint) — Core Web Vital measuring loading speed. <2.5s is “Good”.

Link equity (or link juice) — SEO value transferred through hyperlinks.

Long-tail keyword — Multi-word, specific search query. Usually lower volume but higher intent.

M

Manual action — Penalty issued by Google’s human reviewers. Reportable via Search Console.

Meta description — HTML meta tag with page summary. Appears as snippet in search results.

Mobile-first indexing — Google primarily indexes the mobile version of pages (since 2019).

N

noindex — Meta tag value telling crawlers NOT to index a page.

nofollow — Link attribute discouraging crawler from following. Since 2020, treated as a hint by Google.

O

OpenGraph — Meta tag protocol for social media previews. Originally from Facebook.

Organic traffic — Visitors from unpaid search results (vs paid ads).

P

PageRank — Google’s original algorithm for ranking pages by link structure. Still part of the modern algorithm (just one of many signals).

Position — Average ranking of your URL for a query. Lower is better (1 is best).

Prerender — Generate HTML at build time (SSG). Opposite of runtime rendering.

PWA (Progressive Web App) — Web app with app-like features (offline, push notifications, install).

Q

Query — A user’s search input.

R

Rich result (or Rich Snippet) — Enhanced search result with extra info (stars, prices, FAQ accordions). Powered by structured data.

robots.txt — File at site root telling crawlers what to access. See robots.txt guide.

S

Schema.org — Vocabulary for structured data. Owned consortium of Google, Bing, Yahoo, Yandex.

SERP (Search Engine Results Page) — The page of results for a query.

Sitemap — XML file listing site URLs for crawlers. See Sitemap (Backend).

Soft 404 — Page returning 200 status but appearing empty/not-found. Anti-pattern.

SSL/TLS — Encryption protocols. HTTPS uses TLS.

SSG (Static Site Generation) — Pre-render HTML at build time.

SSR (Server-Side Rendering) — Render HTML on request.

T

TBT (Total Blocking Time) — Lab metric for main-thread blocking. Lab proxy for INP.

TTFB (Time to First Byte) — Server response time. Affects LCP.

TTI (Time to Interactive) — When the page is fully interactive. Mostly replaced by INP.

U

URL (Uniform Resource Locator) — Address of a web resource.

UTM parameters — Query string parameters for campaign tracking. Should canonical to clean URL.

W

WCAG (Web Content Accessibility Guidelines) — Accessibility standards. AA is the practical target.

WebP / AVIF — Modern image formats with better compression than JPG/PNG.

X

x-default — Hreflang value for users whose language matches no explicit alternative.

XML sitemap — Standard sitemap format. See Sitemap (Backend).

Y

YMYL (Your Money or Your Life) — Google’s term for content that could affect a user’s health, finances, safety. Held to higher E-E-A-T standards.