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# \[] == !\[]

JavaScript, the ubiquitous language of the web, is known for its quirks and peculiarities. One such enigma that often baffles both novice and experienced developers is the expression \[] == !\[]. This seemingly simple comparison results in true, leading many to exclaim, "WTF, JavaScript?!". Let's dive into the mechanics behind this puzzling behavior and uncover the logic (or lack thereof) that drives it.

#### See Video

{% embed url="<https://www.youtube.com/watch?v=XPf4KMWPVFo>" %}

####

#### Step-by-Step Explanation

1. **Starting with `![]`:**
   * `[]` is an empty array.
   * When you put `!` (which means "not") in front of something, it turns it into its opposite.
   * An empty array is kind of like saying "something exists" (so it's like `true`).
   * `![]` means "not an empty array," which is like saying "not true," so it becomes `false`.
2. **Now we have `[] == false`:**
   * So now our comparison is `[] == false`.
   * `==` is used to check if two things are equal.
3. **Type Coercion:**
   * JavaScript tries to make different things look the same when comparing them. This is called "type coercion."
   * When comparing an array (`[]`) and a boolean (`false`), JavaScript converts both to numbers.
4. **Converting `false` to a Number:**
   * `false` becomes `0`.
5. **Converting `[]` to a Number:**
   * An empty array (`[]`) becomes an empty string `""`.
   * An empty string `""` becomes `0`.
6. **Final Comparison:**
   * Now we have `0 == 0`, which is `true`.

#### Putting It All Together

* Imagine you have an empty box (`[]`).
* `![]` asks, "Is this box not empty?" Since it is empty, the answer is `false`.
* When you compare the empty box to `false`, JavaScript turns both into `0`.
* Since `0` is equal to `0`, the final result is `true`.

So, `[] == ![]` is `true` because JavaScript does some magic behind the scenes to turn the empty box and `false` into the same thing (both `0`), and then says they are equal.


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