SEO Glossary

Plain-English definitions of the SEO terms that actually matter.

Alt text

A text description of an image, read by screen readers and used by Google to understand images. Improves accessibility and image SEO.

Anchor text

The clickable text of a link. Descriptive anchor text helps search engines understand the linked page.

Backlink

A link from another website to yours. High-quality backlinks are one of the strongest ranking signals.

Canonical URL

A tag that tells search engines which version of a duplicate/similar page is the "master" to index, preventing duplicate-content issues.

CLS (Cumulative Layout Shift)

A Core Web Vital measuring unexpected layout movement while a page loads. Aim for under 0.1.

Core Web Vitals

Google's set of user-experience metrics (LCP, CLS, INP) that directly influence rankings.

Crawl budget

The number of pages a search engine will crawl on your site in a given time. Wasting it on low-value URLs hurts indexing.

Crawlability

How easily search engine bots can access and navigate your site's pages.

E-E-A-T

Experience, Expertise, Authoritativeness, Trust — quality signals Google uses to evaluate content, especially in sensitive niches.

Hreflang

An attribute that tells Google which language/region a page targets, for multi-language sites.

Indexing

The process of a search engine storing a page so it can appear in results. Crawling ≠ indexing.

INP (Interaction to Next Paint)

A Core Web Vital measuring responsiveness to user input. Replaced FID in 2024. Aim for under 200ms.

JSON-LD

The recommended format for structured data — a script that describes your content to enable rich results.

Keyword cannibalization

When multiple pages target the same keyword and compete with each other, weakening all of them.

LCP (Largest Contentful Paint)

A Core Web Vital measuring how fast the largest visible element loads. Aim for under 2.5s.

Meta description

The summary shown under your title in search results. Influences click-through rate. 150-160 characters ideal.

noindex

A directive telling search engines not to show a page in results. The page can still be crawled.

nofollow

A link attribute telling search engines not to pass ranking authority through that link.

Open Graph

Meta tags that control how your page looks when shared on social media (title, description, image).

Organic traffic

Visitors who arrive from unpaid search engine results.

Rich results

Enhanced search listings (stars, FAQs, images) enabled by structured data.

Robots.txt

A file at your site root that tells crawlers which URLs they may or may not crawl.

Schema markup

Structured data (usually JSON-LD) that describes your content type to search engines.

SERP

Search Engine Results Page — the page of results Google shows for a query.

Sitemap (XML)

A file listing your important URLs to help search engines discover and crawl them.

Structured data

Machine-readable markup that describes your content, enabling rich results.

Title tag

The clickable headline in search results and browser tabs. The single strongest on-page element. 50-60 characters ideal.

TTFB (Time to First Byte)

The time from request to the first byte of server response. A slow TTFB delays everything, including LCP.

Canonicalization

The process of selecting the preferred URL when several show the same content.

Crawl-delay

A robots.txt directive requesting bots wait between requests, to reduce server load.