> For the complete documentation index, see [llms.txt](https://docs.guardianservice.app/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.guardianservice.app/learn/important-concepts.md).

# Important Concepts

- [Types of Users](https://docs.guardianservice.app/learn/important-concepts/types-of-users.md)
- [About the Trust Chain](https://docs.guardianservice.app/learn/important-concepts/about-the-trust-chain.md)
- [About Schemas](https://docs.guardianservice.app/learn/important-concepts/about-schemas.md)
- [About Policies](https://docs.guardianservice.app/learn/important-concepts/about-policies.md)
- [About Dry Run](https://docs.guardianservice.app/learn/important-concepts/about-dry-run.md)
- [About Retirement](https://docs.guardianservice.app/learn/important-concepts/about-retirement.md)
- [About MGS Vault](https://docs.guardianservice.app/learn/important-concepts/about-mgs-vault.md)