How to work with the File System (fs) module?

const fs = require('fs');
const fsPromises = require('fs/promises');

// Synchronous (blocks)
const data = fs.readFileSync('file.txt', 'utf8');

// Callback
fs.readFile('file.txt', 'utf8', (err, data) => {
  if (err) throw err;
  console.log(data);
});

// Promise (recommended)
const data = await fsPromises.readFile('file.txt', 'utf8');

// Write (overwrites)
await fsPromises.writeFile('file.txt', 'Hello World');

// Append
await fsPromises.appendFile('file.txt', '\nNew line');

// Check if exists
const exists = fs.existsSync('file.txt');

// Create directory
await fsPromises.mkdir('newDir', { recursive: true });

// List directory
const files = await fsPromises.readdir('.');

// Delete file
await fsPromises.unlink('file.txt');

// Delete directory
await fsPromises.rmdir('dir');
await fsPromises.rm('dir', { recursive: true });

// Rename/Move
await fsPromises.rename('old.txt', 'new.txt');

// Get file info
const stats = await fsPromises.stat('file.txt');
console.log(stats.size, stats.isDirectory());