13) Node OS Module

Introduction
The os module in Node.js is a core module that provides information about the operating system (OS) your Node application is running on. It helps you write programs that are aware of system-level details like CPU, memory, platform, and more.
os is a core Node.js module
Provides system-level information
Common methods: platform(), arch(), cpus() totalmem(), freemem() hostname(), uptime()
Used for:
Performance monitoring
Scaling apps
Environment detection

Why Use the os Module?
You use it when you need:
System information (CPU, memory)
Platform-specific logic
Performance monitoring
Debugging or logging environment details

Commonly Used Methods
i) OS Platform

console.log(os.platform());

// Output
// win32
// linux
// darwin (Mac)

ii) CPU Architecture

console.log(os.arch());

// x64, arm

iii) CPU Info

console.log(os.cpus());

/* Returns array of CPU cores with:
model
speed
times (user, idle, etc.) */

iv) Total Memory

console.log(os.totalmem());

// in bytes

v) Free Memory

console.log(os.freemem());

vi) Hostname

console.log(os.hostname());

vii) OS Type

console.log(os.type());
// Linux
// Windows_NT

viii) Example

const os = require('os');

console.log('Platform:', os.platform());
console.log('CPU Arch:', os.arch());
console.log('Total Memory:', os.totalmem());
console.log('Free Memory:', os.freemem());
console.log('CPUs:', os.cpus().length);

Real-World Use Cases
i) Performance Monitoring
Check memory usage
CPU load
ii) Environment Detection

if (os.platform() === 'win32') {
  console.log('Running on Windows');
}

iii) Scaling Apps
Decide number of workers based on CPU cores

const numCPUs = os.cpus().length;

iv) Logging & Debugging
Capture system details in logs