Web front-end JavaScript consists of:
ECMAScript, (is the JS standard, JS is its implementation and extension, it describes the language of the syntax and basic objects, such as: syntax, operators, statements, inheritance mechanisms, data structures and some built-in objects)
Dom (Document Object Model), describes the method and interface for processing Web page content, parses the entire document file into a DOM tree for users to use JS to process the document.
A BOM (Browser object model) that describes the methods and interfaces (object structures) that can interact with the browser window, such as the Window object, history, location, navigator, and so on.
Nodejs In addition to the language base ECMAScript, there are OS (operating system), file System (FileSystem), net (network system), database, etc., the function modules required for server processing, such as Java is the service-side language in addition to the language itself, It also has the ability to process files, network communications, and so on. Front-end JavaScript runs in a browser environment, so it also includes the object model that is specific to both the DOM and the BOM in the browser environment.
Refer to: 1190000006154835
What is the difference between Nodejs and web front-end JavaScript