This simple Jupyter notebook -- written to accompany a Nature Toolbox feature published on 30 October 2018 -- demonstrates how the computational notebook format allows users to interleave text, code, and results in a single file.

But, unless you have Jupyter notebook installed on your computer, all you can do is view the notebooks, not play with them. (See for yourself: If you click My_sample_notebook.ipynb in this GitHub repository, you will be able to read the notebook, but only as a static document.) This is where Binder and Google's Colaboratory environment come in. Binder is a free, open-source web service that packages Jupyter notebooks inside an executable container, which can be run within a web browser, no installation required. Colab allows users with Google accounts to execute Jupyter notebooks on the Google cloud.

To use Binder:

1. Click the launch binder button above. Once the demo launches, click My_sample_notebook.ipynb in the file listing.
2. Run the notebook by selecting Cell > Run All.
3. Take a look at the graph below the fifth cell (labeled 'The First 25 Fibonacci Numbers').
4. Uncomment the line in the fifth cell that reads # ax.plot (range(25), ar) by removing the leading hashtag (#)
5. Click Cell > Run All again. You should see a change in the graph below that cell.

To use Colab:

1. Click the Open in Colab button above. It will launch the notebook directly.
2. Make the notebook live by clicking 'Connect' in the Colab toolbar.
3. You'll need to uncomment a few lines of code to make the notebook work. Navigate to the first cell, which reads:
   # !pip install biopython
# !pip install folium
# !curl -O https://raw.githubusercontent.com/jperkel/example_notebook/master/NC_005816.gb
4. Uncomment this cell by removing the three leading #.
5. Select Runtime > Run All in the menu to execute the notebook. (You may get a warning that the page was not authored by Google.)
6. Take a look at the graph below the fifth cell (labeled 'The First 25 Fibonacci Numbers').
7. Uncomment the line in the fifth cell that reads # ax.plot (range(25), ar) by removing the leading hashtag (#)
8. Click Runtime > Run All again. You should see a change in the graph below that cell.