JavaScript (Wikipedia)
JavaScript (or JS) is a high level, interpreted scripting language that follows ECMAScript specification.
Widely used, together with HTML and CSS, as core part of World Wide Web technologies.
Benchmark: node.js vs C++:
https://benchmarksgame-team.pages.debian.net/benchmarksgame/fastest/node-gpp.html
JavaScript tutorial
https://www.w3schools.com/js/