---
myst:
  html_meta:
    "description": "Why pas.plugins.identity is built the way it is, and what it deliberately refuses to do."
    "property=og:description": "Why pas.plugins.identity is built the way it is, and what it deliberately refuses to do."
    "property=og:title": "Concepts"
    "keywords": "Plone, pas.plugins.identity, concepts, design, architecture"
---

# Concepts

Explanation is a discursive treatment of a subject, that permits reflection.
Explanation is understanding-oriented.

These pages are about design decisions, not tasks.
Read them when you want to know why something works the way it does, or why it refuses to do something you expected.

Start with {doc}`mental-model`. It names everything the other pages assume.

```{toctree}
:maxdepth: 1

mental-model
identities
layers
email-verification
users-as-content
profiles-and-groups
secrets
federation
threat-model
```