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The core ecosystem of JavaScript consists of 3 main components which are ECMAScript, JavaScript Engine, and the JavaScript Runtime. NodeJS and Google Chrome can use the same JavaScript Engine and yet have very different implementations of JavaScript for developers. The Document Object Model is a language-neutral interface for XML as well as HTML that maps out the entire document as a hierarchy of nodes creating a tree-like representation. JavaScript is a scripting language based on the standards defined in ECMA-262 and is not tied to web browsers.