# Open your first interactive session

An **interactive session** is a running EugoIDE instance attached to your [workspace](/glossary/workspace). It is where you
write code, not where code runs at scale. That happens on a cluster, covered in the
[next lesson](./05-first-cluster.mdx).

## Starting one

From the dashboard, open your [organization](/glossary/organization), choose a workspace, and start a session. Provisioning
takes a few moments; the session is ready when EugoIDE loads in the browser.

If you have no workspace yet, someone with an admin role needs to create one. See
[workspaces & organizations](/courses/workspaces-and-organizations).

## What you are looking at

EugoIDE is a JupyterLab environment. Three regions matter on day one:

**File browser (left).** Your workspace's [persistent storage](/glossary/persistent-storage). Files here survive between sessions.

**Notebook area (center).** Where you write and run Python, cell by cell.

**EugoHPC Manager (right).** Where you launch, monitor, and shut down clusters. Covered next.

## The thing to get right immediately

Not everything you create survives.

| Location | Survives a session restart? |
| --- | --- |
| Workspace storage (the file browser tree) | Yes |
| `/tmp` and other session-local paths | **No** |
| Installed packages, installed into the workspace | Yes |
| Packages installed only into a session's runtime | **No** |

The failure mode is predictable and annoying: an afternoon of work saved to a session-local path,
gone after a restart. Save to the workspace tree.

## Verify it works

Run this in a new notebook:

```python
import sys
import numpy as np
import pandas as pd

print(sys.version)
print(f"numpy {np.__version__}, pandas {pd.__version__}")
```

You should see Python 3.12 and version numbers for both libraries. If that works, your session is
healthy and the scientific stack is available.

## Installing something extra

If you need a package that is not preinstalled:

```python
%pip install some-package
```

For anything the whole team needs, install it into the workspace rather than having each person
install it into their own session. Otherwise every new session pays the setup cost again.

## A session costs money while it is open

A session holds resources whether or not you are typing in it. Close it when you stop for the day.
This is a smaller line item than an [idle cluster](/glossary/idle-cluster), but it is the same category of mistake, and it adds
up across a team.

---

Source: https://university.eugo.io/lesson/getting-started-with-eugo/first-session