JavaScript in 30 words
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JavaScript Closures Explained Simply

The combination of a function and the environment in which it was declared. In Javascript all functions form closures. A common use case is creating private functions.

function createCounter() {
  let count = 0;
  return function increment() {
    count += 1;
    return count;
  };
}
const next = createCounter();
console.log(next());
console.log(next());

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