JS File Documentation


JS format files contain JavaScript source code designed to execute specific instructions on various websites. The data stored in files with the JS extension may include functions that are responsible for closing and opening windows, drop-down menus or checking form fields.

Files with the JS extension are presented in the form of a text file, so they can be opened with any text editor.


Overview

Feature Value
File Extension .js - The standard file extension for JavaScript files.
MIME Type application/javascript - The media type used when transferring JavaScript files over HTTP.
File Type Text - JavaScript files are text-based and can be edited with any text editor.
Primary Usage Client-side and Server-side Scripting - Used both in the browser and on the server (Node.js).
Encoding UTF-8, UTF-16, ISO-8859-1 - Various character encodings supported.
Asynchronous Support Yes (Callbacks, Promises, Async/Await) - Supports asynchronous operations for non-blocking code execution.
Object-Oriented Yes - Supports object-oriented programming with prototypal inheritance.
Functional Programming Yes - Supports functional programming paradigms like first-class functions.
Case Sensitivity Yes - JavaScript is case-sensitive, meaning variable names like 'myVar' and 'myvar' would be considered different.
Comments Single-line and Multi-line - Supports both single-line (//) and multi-line (/* */) comments for code documentation.
Variable Declaration var, let, const - Various keywords for variable declaration, each with its own scoping rules.
Data Types Number, String, Boolean, Array, Object, Null, Undefined - Supports multiple data types for versatile coding.
Error Handling try-catch blocks - Provides structured error handling through try-catch blocks.
Module Support CommonJS, ES6 Modules - Allows code modularization through various module systems.
Popular Libraries jQuery, Lodash, D3.js - Numerous libraries available for extended functionalities.
Popular Frameworks Angular, React, Vue.js - Various frameworks that offer structured development environments.
Server-side Usage Node.js - Enables server-side scripting and full-stack development.
Debugging Tools Console methods, Browser DevTools, Debuggers - Multiple tools and methods for effective debugging.
Regular Expressions Yes - Supports regular expressions for pattern matching.
Event Handling Yes - Provides an event model for handling user interactions like clicks, form submissions, etc.
DOM Manipulation Yes - Allows manipulation of the Document Object Model (DOM) for dynamic content.
JSON Support Yes - Native support for JSON parsing and stringification.
Concurrency Model Event Loop - Utilizes an event loop for handling asynchronous operations.