Add instructions on using Renku (#339)

* Add basic instructions on using Renku

* Address review suggestions

Author: edoardob90

00_intro.ipynb

@@ -18,6 +18,7 @@
     "- [Timetable](#Timetable)\n",
     "- [How to interact](#How-to-interact)\n",
     "- [How to run the tutorial](#How-to-run-the-tutorial)\n",
+    "    - [On Renkulab](#On-RenkuLab)\n",
     "    - [With GitHub Codespaces](#With-GitHub-Codespaces)\n",
     "    - [With Binder](#With-Binder)\n",
     "    - [On your laptop](#On-your-laptop)\n",
@@ -27,7 +28,7 @@
     "    - [Simple view](#Simple-view)\n",
     "    - [File browser](#File-browser)\n",
     "    - [Terminal](#Terminal)\n",
-    "- [Exercises 🌶️](#Exercises-🌶️)\n",
+    "- [Exercises](#Exercises)\n",
     "    - [Exercise example](#Exercise-example)\n",
     "    - [Exercise variables](#Exercise-variables)\n",
     "    - [Exercise difficulty](#Exercise-difficulty)\n",
@@ -103,6 +104,80 @@
     "We designed the tutorial as a hands-on workshop. You should try to write as much code as possible to practice the foundational concepts."
    ]
   },
+  {
+   "attachments": {},
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "## On RenkuLab\n",
+    "\n",
+    "### What is Renku?\n",
+    "\n",
+    "Renku (or RenkuLab) is a platform developed by the Swiss Data Science Center.\n",
+    "Its goal is to bring data and code together by creating **interactive sessions**, where you can do any analysis and seamlessly share with others.\n",
+    "\n",
+    "Two concepts are central to Renku:\n",
+    "\n",
+    "- A **project** is the place where you connect your work (done interactively via JupyterLab, for example), your code repositories (from GitHub or GitLab), and your data (Renku supports multiple providers).\n",
+    "- A **session** is an interactive run-time environment that can be used to do work on data and code. A session is a running instance of a predefined environment. Inside a session, all the project's code repositories are cloned and the data are mounted.\n",
+    "\n",
+    "For this tutorial, we already created a project and prepared the environment to launch new sessions.\n",
+    "Your only tasks are to create (or login to) an account on Renku and then start a new session that you will use for the entire tutorial.\n",
+    "\n",
+    "### Create an Account on Renku\n",
+    "\n",
+    "1. Visit [RenkuLab](https://renkulab.io)\n",
+    "2. Click on **Login** at the top right corner\n",
+    "3. Sign up using your preferred option (edu-ID, GitHub, or ORCID)\n",
+    "\n",
+    "### Start a New Session\n",
+    "\n",
+    "After you created your account, go back to the [tutorial GitHub's page](https://github.com/empa-scientific-it/python-tutorial) and click on the Renku badge to start a new session:\n",
+    "\n",
+    "<img src=\"images/start_renku_session.png\" alt=\"Start a new Renku session\" width=\"800\"/>\n",
+    "\n",
+    "By clicking on the Renku badge link, you will automatically start a new session of the **Python Tutorial Launcher**.\n",
+    "This is the default launcher we are going to use for the whole tutorial.\n",
+    "If you terminate the session and need to start a fresh one, always choose \"Python Tutorial Launcher\".\n",
+    "\n",
+    "### Working in a Session\n",
+    "\n",
+    "Once your session starts, you'll be in a **JupyterLab environment** where you can work with notebooks, Python files, and terminal commands.\n",
+    "\n",
+    "#### Essential Things to Know\n",
+    "\n",
+    "**Saving your work**\n",
+    "- Your work is automatically saved within the session, but you can always *manually* save the notebook you are working on\n",
+    "- Files are located in `/home/jovyan/work/` - this is your working directory inside the session (but you shouldn't worry about that)\n",
+    "- To preserve changes permanently, you need to commit and push them (we'll cover this in the tutorial)\n",
+    "\n",
+    "**Session management**\n",
+    "- Sessions **auto-pause after 30 minutes of inactivity** to save resources\n",
+    "- You can resume a paused session from where you left off - your work won't be lost\n",
+    "- **Always stop your session when done**: Click the session controls (top right) and select \"Stop session\"\n",
+    "\n",
+    "**Installing packages**\n",
+    "- The environment already has the necessary Python packages installed\n",
+    "- You can install other packages with a standard `pip install <package-name>` in a Terminal window\n",
+    "    - **Note:** Packages installed this way are temporary and only last for your current session\n",
+    "\n",
+    "\n",
+    "<img src=\"images/open_terminal.png\" alt=\"Open a new Terminal\" width=\"500\"/>\n",
+    "\n",
+    "\n",
+    "**Starting fresh**\n",
+    "- The first time you start a session, it may take 1-2 minutes to build the environment\n",
+    "- If something breaks, you can always stop the session and start a new one\n",
+    "\n",
+    "### Troubleshooting\n",
+    "\n",
+    "| Problem | Solution |\n",
+    "|---------|----------|\n",
+    "| Session won't start | Wait 1-2 minutes - the environment is building |\n",
+    "| Lost your work | If you didn't stop the session, your files are still there. Resume the session to continue |\n",
+    "| Something broke | Stop the current session and start a fresh one |"
+   ]
+  },
   {
    "cell_type": "markdown",
    "metadata": {},
@@ -368,7 +443,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "# Exercises 🌶️\n",
+    "# Exercises\n",
     "\n",
     "For each topic we prepared a bunch of exercises to practice the concepts.\n",
     "\n",
@@ -553,7 +628,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.10.17"
+   "version": "3.12.12"
   },
   "vscode": {
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