Clerk

1. Core concepts

   Users, sessions, organizations and instances.

2. How Clerk works

   Clerk architecture including cookies, tokens and frontend and backend APIs.

3. Sign-up and sign-in options

   Configuring identifiers, passwords, social connections and other authentication strategies.

4. Session tokens

   Session tokens, their claims, lifetime and refresh.

5. Verifying sessions

   Verifying session JWTs on your own backend.

6. User management

   Managing users, metadata, invitations and impersonation.

7. Organizations

   Organizations, members and multi-tenant features.

8. Roles and permissions

   Organization roles, permissions and authorization checks.

9. Customization

   Appearance, localization, email templates.

10. Security

    Bot protection, MFA, password rules.

11. Webhooks

    Webhooks that sync Clerk events like user.created to your database.

12. Billing

    Billing plans, subscriptions and entitlements.

13. Environments and deployment

    Development and production instances, domains and deployment.

14. Testing

    Test emails and phone numbers and testing tokens for automated tests.

15. System limits

    System limits and rate limits applied to Clerk APIs.

Each section links to the official page. Titles and summaries by Extra Credit; the docs belong to their authors.