*.ipynb file extension is used for computational notebooks that can be open with Jupyter Notebook. The Jupyter Notebook was formerly named IPython Notebook. The extension
*.ipynb is from letters IPython Notebook. The IPython was developed as a command shell for interactive computing in Python programming language. It offers introspection, rich media, shell syntax, tab completion, and history.
The Jupyter notebooks provide great flexibility for developing Python programs. The code is organised in cells, and execution results are presented just below the cell. This approach gains huge trackion among programmers, especially data scientists, around the globe. To make the notebooks more accessible to non-programmers there is possible to add an interactive widgets to the notebook. What is more, such notebook can be shared as standalone web application, which greatly simplifies the sharing. In this article I will present two alternative approaches for adding widgets into Jupyter Notebook, namely ipywidgets+Voila and Mercury.