Node.js is an open-source, cross-platform JavaScript run-time environment that executes JavaScript code outside of a browser. JavaScript is used primarily for client-side scripting, in which scripts written in JavaScript are embedded in a webpage’s HTML and run client-side by a JavaScript engine in the user’s web browser. wiki
Project Jupyter (/ˈdʒuːpɪtər/ (About this soundlisten)) is a nonprofit organization created to “develop open-source software, open-standards, and services for interactive computing across dozens of programming languages”.
A heat map (or heatmap) is a graphical representation of data where the individual values contained in a matrix are represented as colors. “Heat map” is a newer term but shading matrices have existed for over a century. wiki