Node.js

Server-side JavaScript development with Node.js - build scalable backend applications

Node.js is a JavaScript runtime built on Chrome’s V8 engine that allows you to run JavaScript on the server-side. It enables developers to use JavaScript for full-stack development, from frontend to backend.

Key Characteristics

Event-Driven Architecture: Built on an event loop for handling asynchronous operations
Non-Blocking I/O: Handles multiple concurrent connections efficiently without creating threads per connection
Package Ecosystem: Access to millions of packages via npm
Single-Threaded Model: Simplified development model, though multi-threading is possible with Worker Threads
Cross-Platform: Run the same code on Windows, macOS, and Linux

Common Use Cases

REST APIs and Web Services: Build fast, scalable backend APIs
Real-Time Applications: WebSocket servers, chat applications, live updates
Microservices: Lightweight services that communicate over HTTP/gRPC
CLI Tools: Command-line utilities and automation scripts
Data Processing: ETL pipelines and data transformation tools
Streaming Applications: Process large files and streams efficiently

Core Modules

Node.js provides built-in modules for common tasks:

fs: File system operations (read, write, delete files)
http: Create HTTP servers and clients
path: Handle file and directory paths
events: Event emitter pattern implementation
stream: Work with streaming data
crypto: Cryptographic functionality
util: Utility functions

Getting Started

# Check Node.js version
node --version

# Run JavaScript file
node app.js

# Initialize a project
npm init -y

# Install packages
npm install express

# Run scripts defined in package.json
npm run start

Application Structure

A typical Node.js application includes:

package.json: Project metadata and dependencies
src/: Application source code
node_modules/: Installed packages (excluded from version control)
.env: Environment variables
.gitignore: Files to exclude from git

Next Steps

Learn about Node.js fundamentals, async patterns, file operations, HTTP servers, performance optimization, and best practices for building production-ready applications.