I'm trying to beef up my understanding of Vue, and I noticed that in the docs on event handling, they say:

"You can pass it into a method using the special $event variable, or use an inline arrow function:"

<button @click="warn('Form cannot be submitted yet.', $event)">
  Submit
</button>

<!-- using inline arrow function -->
<button @click="(event) => warn('Form cannot be submitted yet.', event)">
  Submit
</button>

But they never elaborate on the $event var, or what makes it special. Does anyone here know?