JavaScript is a …
JavaScript is the Language of the Web.
It allows us to write scripts much like a movie or a play, but in an interactive fashion.
We can detail how elements will behave on a web page. But not only…
Most commonly used to define behavior web applications.
User interactions, manipulating the browser, communicate
asynchronously, and alter the document content that is
displayed.
It is also being used in server-side programming (with
Node.js), game development and the creation of desktop and
mobile applications.
— Wikipedia