---
title: Concepts
path: concepts
status: published
---

# Concepts

The vocabulary and mental model you need to use ScaiKey effectively. Read these in order if you're new; jump around if you're not.

- **[Architecture](/docs/scaikey/concepts/architecture)** — how partners, tenants, users, and applications fit together.
- **[OAuth and OIDC](/docs/scaikey/concepts/oauth-and-oidc)** — which grants ScaiKey supports and when to pick each.
- **[Tokens and scopes](/docs/scaikey/concepts/tokens-and-scopes)** — what's inside a ScaiKey JWT, how scopes constrain access, how Token Exchange works.
- **[Applications](/docs/scaikey/concepts/applications)** — the four app types, the three scope levels, and what each combination means in practice.

If you're trying to *do* something rather than understand the model, [Tutorials](/docs/scaikey/tutorials) is the right starting point.