Quite simply, Project Jupyter exists to develop open-source software, open-standards, and services for interactive computing across dozens of programming languages primarily through the Jupyter Notebook.
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. The user interface supports a wide range of workflows in data science, scientific computing, and machine learning. Notebooks can be shared with others using email, Dropbox, GitHub and the Jupyter Notebook Viewer. Jupyter allows you to configure and arrange the user interface to support a wide range of workflows in data science, scientific computing, and machine learning. It's also extensible and modular, meaning you can write plugins that add new components and integrate with existing ones. Your code can produce rich, interactive output: HTML, images, videos, LaTeX, and even custom MIME types.
You can find out more about Jupyter and what it's capable of by visting the project website: https://docs.jupyter.org/en/latest/#start-here