...The Jupyter Notebook is an open-source web application that allows you to create and share documents that contain live code, equations, visualizations and narrative text.
Calling it "live" seems just slightly inaccurate to me. Every time code needs to run an http request needs to be made. (Unless there's some new tech here I'm unaware of)
This is a limitation that may make no difference in some cases, but in others it is important for code to execute in the client.
A good example of this is making a visualization that seamlessly responds to the user's mouse pointer.
everyone has a web browser...