Forgetful Notes

Node.js

Node.js is a JavaScript runtime built on Chrome’s V8 JavaScript engine. It allows developers to write server-side applications in JavaScript, breaking the language free from its traditional confines within the web browser. Node.js is known for its non-blocking, event-driven architecture, which makes it highly efficient and suitable for building scalable network applications.

Info

The core philosophy of Node.js is to handle many connections with high throughput, making it ideal for I/O-intensive applications like web servers, API backends, and real-time services.

Core Architecture

  • Event-Driven, Non-Blocking I/O: Node.js uses an event loop to handle asynchronous operations. Instead of waiting for a task (like reading a file or a database query) to complete, it registers a callback and moves on to the next task. This allows it to handle thousands of concurrent connections with a single thread.
  • V8 Engine: It uses Google’s V8 engine, the same one that powers Chrome, which compiles JavaScript into machine code for high performance.
  • Module System: Node.js has a built-in module system (CommonJS) that allows you to organize code into reusable files.

Key Features

  • NPM (Node Package Manager): Node.js comes with NPM, the world’s largest software registry. It provides access to hundreds of thousands of open-source libraries and tools.
  • Standard Library: Includes a rich library of modules for file system operations, networking, and more.
  • Cross-Platform: Runs on Windows, macOS, and Linux.

Example: A Simple Web Server

const http = require('http');
 
const hostname = '127.0.0.1';
const port = 3000;
 
const server = http.createServer((req, res) => {
  res.statusCode = 200;
  res.setHeader('Content-Type', 'text/plain');
  res.end('Hello, World!\n');
});
 
server.listen(port, hostname, () => {
  console.log(`Server running at http://${hostname}:${port}/`);
});

Use Cases

  • Backend APIs: Building RESTful and GraphQL APIs for web and mobile applications.
  • Real-Time Applications: Powering chat applications, online games, and collaborative tools using technologies like WebSockets.
  • Microservices: Creating small, independent services that make up a larger application.
  • Tooling: Building command-line tools, build scripts, and other development utilities.

Node.js has become a dominant force in web development, enabling developers to use JavaScript across the entire stack. Its vast ecosystem, managed by package managers like NPM and PNPM, provides tools for nearly any task.

Graph View

Backlinks