Technical SEO basics

The HTML and markup fundamentals every engine — and every AI — uses to understand a page.

12 lessons

1. 01

   How a search engine (and an AI) reads your page

   A crawler doesn't see your page like a visitor does: it fetches raw HTML, sometimes without a JavaScript render, then extracts text split into chunks.

2. 02

   The title tag

   The title tag's real role, recommended length, and how to write it around a clear intent and entity, with before/after examples to guide you.

3. 03

   The meta description

   It doesn't directly affect ranking, but it shapes clicks and how an AI summarizes your page. How to write one that informs instead of just filling space.

4. 04

   Heading tags (H1, H2, H3)

   A clean heading hierarchy, a single H1, and H2s phrased as questions: what helps an engine and an AI understand your page.

5. 05

   The canonical tag

   How to indicate the reference version of a page duplicated by URL parameters, and avoid mistakes that deindex entire pages.

6. 06

   Open Graph tags

   How to control your page's preview on social media and in AI chats: the og:title, og:description, and og:image tags explained.

7. 07

   The hreflang tag (multilingual)

   How to signal the right language version of a page to search engines, with correct syntax and the most common reciprocity mistakes.

8. 08

   Redirects and HTTP errors

   301, 302, 308: when to use each redirect type, why to avoid chains, and how 404s and 5xx errors affect crawling.

9. 09

   Semantic HTML5

   article, section, nav, main: why semantic HTML structure helps AIs isolate useful content from noise (menus, footer, ads).

10. 10

    Schema.org structured data: understanding it

    What Schema.org/JSON-LD markup is, and why it gives engines and AIs unambiguous facts (price, reviews, author, dates).

11. 11

    Schema.org structured data: implementing it

    Priority types (Organization, Product, FAQPage, Article, BreadcrumbList), an annotated JSON-LD example, and validation tools.

12. 12

    The complete technical checklist

    20 actionable points to verify markup, URLs, HTTP statuses, and structured data before moving on to content production.