# Core concepts

A small vocabulary shows up throughout the docs and the apps. Learn it once here.

## App

An **app** is a separately deployed product with its own URL and release train: Chat (`chat.upcube.ai`), Studio (`studio.upcube.ai`), and this site (`upcube.ai`, which also serves Model Intelligence). Connected Apps is the user-facing surface of Flow, served through Chat settings and the Platform control plane.

## Connection

A **connection** links your Ethen identity to one account on an external app (for example, one Gmail mailbox). Connections carry their own lifecycle: active, needs-reauth, revoked, and more. See [Managing connections](/docs/connected-apps/managing-connections).

## Scope

A **scope** is one permission a connection grants (for example, read-only mail access). Ethen requests the smallest scope set that satisfies the task, and shows every grant before it runs. Grants you did not approve never run.

## Approval

Sensitive actions pause for an **approval** step: a human confirms the exact action, on the exact account, before anything with real-world effect runs. Approvals expire, and a changed action needs a fresh approval — never a reuse of the old one.

## Evidence

Runs produce an **evidence** trail — what ran, on which account, under which approval, with what outcome — so you can audit and reproduce results. "It worked" is never the whole story; the trail is.

## Lifecycle

Every product carries a truthful **lifecycle**: live, private alpha, beta, preview, or coming. Planned features are labeled planned or roadmap. No mock, fixture, or catalog listing ever establishes that something is live, connected, or certified.

:::tip
Keep these six terms in mind: they map directly onto the product surfaces you will use.
:::

## Next steps

- [Chat overview](/docs/chat/overview)
- [Connected Apps overview](/docs/connected-apps/overview)
- [API reference: Flow](/docs/api/flow)