Node.js vs Browser

Key Differences

Node.js is designed for server - side development, while browsers are for client - side applications.

APIs:

Global Objects:

Node.js uses global
; browsers use window or self.

Modules:

); browsers use ES modules or plain

Security:

Browsers run in a sandbox with limited access; Node.js has full access to the file system and network.

Event Loop:

Environment Variables:

); browsers cannot.

Package Management:

Node.js uses npm/yarn; browsers use CDNs or bundlers.

Examples

Global Objects

// Node.js global.mylet = 42;
console.log(global.mylet); // 42
// Browser window.mylet = 42;
console.log(window.mylet); // 42

File Access

// Node.js const fs = require('fs');
fs.readFile('myfile.txt', 'utf8', (err, data) => {
if (err) throw err;
console.log(data);
});

HTTP Requests

// Node.js const https = require('https');
https.get('https://example.com', res => {
let data = '';
res.on('data', chunk => data += chunk);
res.on('end', () => console.log(data));
});
// Browser fetch('https://example.com').then(response => response.text()).then(console.log);

Modules

const fs = require('fs');
// Node.js & Browser (ES Modules)
// import fs from 'fs'; // Node.js only, not browser
// import _ from 'https://cdn.jsdelivr.net/npm/lodash-es/lodash.js'; // Browser

Comparison Table

Feature

Browser

File System Access

Yes

Networking (TCP/UDP)

Yes

DOM Access

Yes

Global Object global window/self

Modules

CommonJS/ESM