JavaScript is a programming language mostly used to develop web pages/web applications. It is interpreted, Just-in-Time compiled based on engine, eg: v8.
It follows ECMAScript Language Specification and ECMAScript Internationalization API specification. If someone is referring to ES6+ they are referring to JavaScript with the features from that specific ECMAScript version.
There are some popular Javascript libraries like Angular, ReactJs, VueJs which has several options that helps build web applications fast and easy.
Apart from browsers, javascript can be used at server side also using nodejs.
Some of the useful topics to understand are
1.What is interpreted and Just-in-Time Compilation?
2.What is Javascript engine?
3.How javascript code execution will happen?
