Functions and Modules

Functions

function add(a, b) {
  return a + b;
}

const multiply = (a, b) => a * b;

console.log('add(2, 3) =', add(2, 3));
console.log('multiply(4, 5) =', multiply(4, 5));

ES Modules

Split code across files with import/export (module files need a real Node.js project, so this example is read-only):

// math.js
export function add(a, b) {
  return a + b;
}

// app.js
import { add } from './math.js';
console.log(add(2, 3)); // 5

Set "type": "module" in package.json to use ES modules natively.