SEO Terms Glossary - 40+ Search Engine Optimization Terms

This glossary defines common SEO (Search Engine Optimization) terms you will encounter when optimizing websites for search engines.

A

Algorithm

The mathematical rules search engines use to rank web pages. Google's algorithm considers hundreds of factors.

Alt Text

Text describing an image, used by screen readers and search engines. Alt text improves accessibility and image SEO.

Anchor Text

The visible, clickable text in a hyperlink. Anchor text helps search engines understand the linked page's topic.

B

Backlink

A link from another website to yours. Quality backlinks are a significant ranking factor.

Black Hat SEO

Unethical SEO practices that violate search engine guidelines, such as buying links or keyword stuffing. Black hat techniques risk penalties.

C

Canonical Tag

An HTML element that tells search engines which version of a page is the master version, preventing duplicate content issues.

Crawl

The process by which search engines discover web pages by following links.

Core Web Vitals

Google's metrics for user experience: LCP (Largest Contentful Paint), INP (Interaction to Next Paint), and CLS (Cumulative Layout Shift).

D

Do-Follow Link

A link that passes SEO value to the linked page. Most links are do-follow by default.

Domain Authority

A score (0-100) predicting how well a website ranks in search results, developed by Moz.

E

E-E-A-T

Experience, Expertise, Authoritativeness, Trustworthiness. Google's framework for evaluating content quality, especially for YMYL topics.

F

Featured Snippet

A summary of an answer to a search query displayed at the top of Google results, extracted from a web page.

I

Index

The database of web pages that search engines have crawled and can display in results.

Internal Link

A link from one page on your site to another page on your site. Internal links help users and search engines navigate.

K

Keyword

A word or phrase that users type into search engines. Keywords are the foundation of SEO strategy.

Keyword Density

The percentage of times a keyword appears on a page relative to total words. Modern SEO does not target specific densities.

L

Long-Tail Keyword

A specific, low-search-volume keyword phrase, typically 3+ words. Long-tail keywords are easier to rank for and convert better.

M

Meta Description

An HTML tag that summarizes a page's content. Meta descriptions appear in search results and influence click-through rate.

Meta Tags

HTML elements in the head section that provide information about a page to search engines and social platforms.

N

Noindex

A meta tag or header that tells search engines not to index a page.

Nofollow

A link attribute that tells search engines not to pass SEO value. Nofollow links do not directly improve rankings.

O

Open Graph

A protocol that controls how pages appear when shared on social media. Open Graph tags include og:title, og:description, og:image.

Organic Traffic

Visitors who arrive from unpaid search engine results, as opposed to paid advertising.

P

Page Authority

A score predicting how well a specific page ranks in search results, developed by Moz.

R

Ranking

The position of a web page in search results for a given query. Higher rankings (position 1) receive more traffic.

Robots.txt

A file at the root of a website that instructs search engine crawlers which pages to crawl and which to ignore.

S

Schema Markup

Structured data using schema.org vocabulary that helps search engines understand page content and enable rich results.

SERP (Search Engine Results Page)

The page displayed by a search engine in response to a query. SERPs include organic results, ads, and rich features.

Sitemap

A file listing all pages on a website, submitted to search engines to help them discover content.

T

Title Tag

An HTML element that defines the page title. Title tags are significant ranking factors and appear in search results.

Traffic

The number of visitors to a website. Traffic sources include organic search, paid ads, social media, and direct visits.

Y

YMYL (Your Money or Your Life)

Google's categorization for pages that could impact health, financial stability, or safety. YMYL pages face higher quality standards.