// Core principles of SEO including E-E-A-T, Core Web Vitals, technical foundations, content quality, and how modern search engines evaluate pages.
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| name | seo-fundamentals |
| description | Core principles of SEO including E-E-A-T, Core Web Vitals, technical foundations, content quality, and how modern search engines evaluate pages. |
| risk | safe |
| source | community |
| date_added | 2026-02-27 |
Foundational principles for sustainable search visibility. This skill explains how search engines evaluate quality, not tactical shortcuts.
E-E-A-T is not a direct ranking factor. It is a framework used by search engines to evaluate content quality, especially for sensitive or high-impact topics.
| Dimension | What It Represents | Common Signals |
|---|---|---|
| Experience | First-hand, real-world involvement | Original examples, lived experience, demonstrations |
| Expertise | Subject-matter competence | Credentials, depth, accuracy |
| Authoritativeness | Recognition by others | Mentions, citations, links |
| Trustworthiness | Reliability and safety | HTTPS, transparency, accuracy |
Pages competing in the same space are often differentiated by trust and experience, not keywords.
Core Web Vitals measure how users experience a page, not whether it deserves to rank.
| Metric | Target | What It Reflects |
|---|---|---|
| LCP | < 2.5s | Loading performance |
| INP | < 200ms | Interactivity |
| CLS | < 0.1 | Visual stability |
Important context:
Technical SEO ensures pages are accessible, understandable, and stable.
| Element | Purpose |
|---|---|
| XML sitemaps | Help discovery |
| robots.txt | Control crawl access |
| Canonical tags | Consolidate duplicates |
| HTTP status codes | Communicate page state |
| HTTPS | Security and trust |
| Factor | Why It Matters |
|---|---|
| Page speed | User satisfaction |
| Mobile-friendly design | Mobile-first indexing |
| Clean URLs | Crawl clarity |
| Semantic HTML | Accessibility & understanding |
| Element | Principle |
|---|---|
| Title tag | Clear topic + intent |
| Meta description | Click relevance, not ranking |
| H1 | Page’s primary subject |
| Headings | Logical structure |
| Alt text | Accessibility and context |
| Dimension | What Search Engines Look For |
|---|---|
| Depth | Fully answers the query |
| Originality | Adds unique value |
| Accuracy | Factually correct |
| Clarity | Easy to understand |
| Usefulness | Satisfies intent |
Structured data helps search engines understand meaning, not boost rankings directly.
| Type | Purpose |
|---|---|
| Article | Content classification |
| Organization | Entity identity |
| Person | Author information |
| FAQPage | Q&A clarity |
| Product | Commerce details |
| Review | Ratings context |
| BreadcrumbList | Site structure |
Schema enables eligibility for rich results but does not guarantee them.
Search engines evaluate output quality, not authorship method.
There is no fixed ranking factor order. However, when competing pages are similar, importance tends to follow this pattern:
| Relative Weight | Factor |
|---|---|
| Highest | Content relevance & quality |
| High | Authority & trust signals |
| Medium | Page experience (CWV, UX) |
| Medium | Mobile optimization |
| Baseline | Technical accessibility |
Technical SEO enables ranking; content quality earns it.
SEO fundamentals should be validated using multiple signals, not single metrics.
| Area | What to Observe |
|---|---|
| Visibility | Indexed pages, impressions |
| Engagement | Click-through, dwell time |
| Performance | CWV field data |
| Coverage | Indexing status |
| Authority | Mentions and links |
Key Principle: Sustainable SEO is built on useful content, technical clarity, and trust over time. There are no permanent shortcuts.
This skill is applicable to execute the workflow or actions described in the overview.