Introduction
## Quick Reference
| Topic | File | |-------|------| | Title tags, meta descriptions, headers, keyword placement | `on-page.md` | | Core Web Vitals, crawlability, mobile, indexing | `technical.md` | | Search intent, E-E-A-T, content freshness | `content.md` | | Google Business, NAP consistency, local keywords | `local.md` | | JSON-LD, Article, LocalBusiness, FAQ, Product schema | `schema.md` | | Internal linking, anchor text, backlink principles | `links.md` |
## Critical Rules
### On-Page Fundamentals - Title: 50-60 chars, primary keyword in first 30 chars, unique per page - Meta description: 150-160 chars, benefit-focused, call-to-action - Only one H1 per page — must differ from title but include primary keyword - H1 → H2 → H3 strict hierarchy — never skip levels - Primary keyword in: title, H1, first 100 words, URL - Keyword density under 3% — stuffing triggers penalties
### Technical Essentials - Core Web Vitals: LCP < 2.5s, INP < 200ms, CLS < 0.1 - Mobile-first indexing: Google indexes mobile version — test mobile rendering - Canonical URL on every page — prevents duplicate content penalties - robots.txt: don't block CSS/JS, Google needs them to render - XML sitemap: max 50K URLs per file, submit in Search Console - HTTPS required — mixed content breaks security indicators
### Content Signals - Search intent match: informational, navigational, transactional, commercial - E-E-A-T for YMYL: Experience, Expertise, Authoritativeness, Trustworthiness - Thin content penalty: pages under 300 words with no unique value - Content freshness: update dates matter for time-sensitive queries
### Penalties to Avoid - Hidden text with CSS or font-size:0 — immediate penalty - Duplicate title tags across pages — wastes crawl budget - Keyword stuffing in alt text — unnatural patterns detected - Cloaking: showing different content to users vs bots - Link schemes: buying links, excessive link exchanges