Manu Kumar Pal

Posted on Jun 28

🚀 JavaScript ES6 Features You Should Know in 2025

#webdev #programming #javascript

Hey DEV community! 👋 ES6 introduced game-changing features every modern JavaScript developer still relies on — and in 2025, they’re more essential than ever! Here’s a quick guide to the must-know ES6 features for writing cleaner, faster, and better code. Let’s dive in! 🏊‍♂️

1️⃣ let and const — Block-Scoped Variables

-> Before ES6, we only had var, which is function-scoped and can cause tricky bugs. ES6 introduced let and const:

let count = 0;        // mutable
const name = "DEV";   // immutable

✅ Use let for values that change
✅ Use const for constants

2️⃣ Arrow Functions ➡️

-> Arrow functions provide shorter syntax and fix this context issues:

const add = (a, b) => a + b;
No more .bind(this) for callbacks!

3️⃣ Template Literals 📝

-> String interpolation becomes a breeze:

const user = "Alice";
console.log(`Hello, ${user}!`);

Also supports multi-line strings without messy \n.

4️⃣** Destructuring** 🧩

-> Unpack arrays or objects easily:

const [first, second] = [10, 20];
const { title, year } = { title: "ES6", year: 2015 };

Perfect for cleaner code when working with props or API responses.

5️⃣** Default Parameters **⚙️

-> Set default values for function arguments:

function greet(name = "Manu") {
  console.log(`Hello, ${name}!`);
}

6️⃣ Rest & Spread Operators ✨

-> Rest: Collects remaining items into an array:

function sum(...nums) {
  return nums.reduce((a, b) => a + b);
}

-> Spread: Expands arrays or objects:

const arr = [1, 2, 3];
const newArr = [...arr, 4, 5];

7️⃣ Enhanced Object Literals 🛠️

-> Define objects with shorthand properties and methods:

const age = 30;
const user = {
  name: "Manu",
  age,
  greet() {
    console.log("Hi!");
  }
};

8️⃣ Promises 🤝

-> Handle async operations more elegantly than callbacks:

fetch("https://api.example.com/data")
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(err => console.error(err));

9️⃣ Modules 📦

-> Break code into reusable files:

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

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

🔚 Conclusion

These ES6 features transformed JavaScript from a simple scripting language into the powerful, modern tool we use today.

DEV Community

🚀 JavaScript ES6 Features You Should Know in 2025

Top comments (0)