---
title: Projects and sessions
description: The two units of organization, and who runs the work.
section: Concepts
order: 1
---

# Projects and sessions

Admiral organizes everything with two units: the project and the session. Understand these two, and the rest of the app reads clearly.

## Project

A project is a folder on one device. It holds the code, and it holds the sessions about that code.

The device that owns the folder is the project's **host**. The host runs the agents. When you open that project from a different device, you see and steer the same sessions, but the work still runs on the host.

This is why a session does not break when you close your laptop: the host, not your laptop, is doing the work.

## Session

A session is one conversation. It belongs to one project. It has one transcript, one composer history, one changes view, and its own terminals.

Each session carries a **hull number**, a short callsign like `A07`, shown next to its name. It is an identity mark, like the number painted on a carrier's aircraft. It means nothing else: it is not a rank, a count, or a score. Callsigns run `A01` to `A99`, then `B01`, and so on to `Z99`; the letter marks the series, not a project.

## Where the work actually runs

Follow one prompt through the system:

1. You type in the composer on any device.
2. The message lands in a durable queue.
3. The host device delivers the message to the agent.
4. The agent runs on the host, inside the project folder.
5. Output streams back to every device watching the session.

Your device is a control station. The host is the flight deck.

## Many agents, one session

A session can change agents and models during its life. The transcript stays. See [Agents and models](agents-and-models.md) for what carries over and what does not.

## Next steps

- [Session states](session-states.md): the colors you will see.
- [Where your data lives](where-your-data-lives.md): storage and sync.