seo-fundamentals
Core principles of SEO including E-E-A-T, Core Web Vitals, technical foundations, content quality, and how modern search engines evaluate pages. This skill explains *why* SEO works, not how to execute specific optimizations.
SEO Fundamentals
> Foundational principles for sustainable search visibility.
> This skill explains _how search engines evaluate quality_, not tactical shortcuts.
1. E-E-A-T (Quality Evaluation Framework)
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.
2. Core Web Vitals (Page Experience Signals)
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:
3. Technical SEO Principles
Technical SEO ensures pages are accessible, understandable, and stable.
Crawl & Index Control
| 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 |
Performance & Accessibility
| Factor | Why It Matters |
|---|---|
| Page speed | User satisfaction |
| Mobile-friendly design | Mobile-first indexing |
| Clean URLs | Crawl clarity |
| Semantic HTML | Accessibility & understanding |
4. Content SEO Principles
Page-Level Elements
| 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 |
Content Quality Signals
| 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 |
5. Structured Data (Schema)
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.
6. AI-Assisted Content Principles
Search engines evaluate output quality, not authorship method.
Effective Use
Risky Use
7. Relative Importance of SEO Factors
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.
8. Measurement & Evaluation
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.