How do closures work in JavaScript, and why are they useful for managing state in functions?

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Q&A Network · Accepted Answer

Closures in JavaScript allow a function to access variables from its outer scope even after the outer function has finished executing. They are useful for managing state because they enable private variables and encapsulation.


        
        function createCounter() {
            let count = 0;
            return function() {
                count += 1;
                return count;
            };
        }

        const counter = createCounter();
        console.log(counter()); // 1
        console.log(counter()); // 2
        console.log(counter()); // 3

ADDITIONAL COMMENT: - The "createCounter" function returns an inner function that has access to the "count" variable. - Each call to "counter()" increments and returns the "count" value, demonstrating how closures maintain state. - Closures are beneficial for data encapsulation, as the "count" variable is not directly accessible from outside the "createCounter" function. ✅ Answered with JavaScript best practices.

How do closures work in JavaScript, and why are they useful for managing state in functions? Pending Review

Asked on Oct 12, 2025

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