How do closures help in JavaScript?

What are closures in JavaScript?

Closures are functions that retain access to their lexical scope, even when the function is executed outside that scope.

Can you give me an example of how closures are used?

Sure! A common use of closures is in creating private variables. Here's an example:

function makeCounter() {
    let count = 0;
    return function() {
        count++;
        return count;
    };
}
const counter = makeCounter();
console.log(counter()); // 1
console.log(counter()); // 2

In this example, count is a private variable that can only be accessed and modified by the inner function.

Why are closures important in JavaScript?

Closures are important because they enable data encapsulation, help manage asynchronous code, and allow for function factories, enhancing modularity and reusability.