ES6 Features

ES6 (ECMAScript 2015) introduced several new features and improvements to JavaScript, making the language more powerful and easier to use. Below are some of the key features of ES6:

1. Let and Const

The let and const keywords provide block-scoping for variables, replacing the older var.

let name = "John";
const age = 30;

name = "Doe"; 
age = 35; 
    

Output: TypeError: Assignment to constant variable

2. Arrow Functions

Arrow functions provide a concise syntax for writing functions and lexically bind the this value.

const add = (a, b) => a + b;
console.log(add(2, 3));
    

Output: 5

3. Template Literals

Template literals allow embedding expressions inside strings using backticks (`) and the ${} syntax.

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

Output: Hello, Alice!

4. Default Parameters

Functions can now have default parameter values.

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

Output: Hello, Guest!

5. Destructuring

Destructuring allows unpacking values from arrays or properties from objects into variables.

const person = { name: "Bob", age: 25 };
const { name, age } = person;
console.log(name, age);
    

Output: Bob 25

6. Modules

ES6 introduced import and export for modular programming.

// file1.js
export const greet = () => console.log("Hello, World!");

// file2.js
import { greet } from './file1.js';
greet(); 
    

Output: Hello, World!

7. Promises

Promises make handling asynchronous operations easier by avoiding callback hell.

const fetchData = new Promise((resolve, reject) => {
    setTimeout(() => resolve("Data loaded"), 2000);
});

fetchData.then(data => console.log(data)); 
    

Output (after 2 seconds): Data loaded

Conclusion

ES6 features bring modern and efficient tools to JavaScript development, making code easier to write and understand.