What does it mean when you write an expression like this const [count, setCount] = useState(0)

Question

I was reading up on React hooks when i stumbled up on this code.

import React, { useState, useEffect } from 'react';

function Example() {
  const [count, setCount] = useState(0);

  // Similar to componentDidMount and componentDidUpdate
  useEffect(() => {
    // Update the document title using the browser API
    document.title = `You clicked ${count} times`;
  });

  return (
    <div>
      <p>You clicked {count} times</p>
      <button onClick={() => setCount(count + 1)}>
        Click me
      </button>
    </div>
  );
}

I'm trying to understand how this declaration const [count, setCount] = useState(0); was later used in this manner setCount(count + 1).

What exactly isn't clear to you? Do you understand how `count` gets a value? Do you understand how `setCount` triggers the component to be refreshed (the function gets executed again) ? — Jonas Wilms, May 02 '19 at 15:25
`const [count, setCount] = useState(0);` and why it could later on be used like this `setCount(count + 1)` — Devops-Paddy, May 02 '19 at 15:27
It looks like you're reading the docs from the [react hooks guide](https://reactjs.org/docs/hooks-state.html) in which they explain [array destructuring on the same page just further down](https://reactjs.org/docs/hooks-state.html#tip-what-do-square-brackets-mean). — chazsolo, May 02 '19 at 15:27
Maybe, giving a read to [destructuring assigment](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/Destructuring_assignment) can give you some light — Shidersz, May 02 '19 at 15:28
The question as is is too broad to be answered. Please read through all the links we provided to you, if there is still something unclear ask a new question stating what exactly you think happens, and what exactly you did not understand. We will be glad to help :) — Jonas Wilms, May 02 '19 at 15:33
Oh okay, thanks everyone. And thank you @Shidersz. I finally understand this method and what it's called in javascript — Devops-Paddy, May 02 '19 at 15:33
@JonasWilms i don't think this question is a duplicate. I believe he needed know about array destructuring — Ikechukwu, May 03 '19 at 08:04

What does it mean when you write an expression like this const [count, setCount] = useState(0)

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