jQuery - Target HTML Elements with Selectors Using jQuery

What does the “animated” class do? When I take out the “animated” class, the button won’t bounce and the well wouldn’t shake. Is the “animated” class part of Bootstrap or jQuery?

I am a beginner and if my question sounds silly, sorry in advance.

  **Your code so far**
$(document).ready(function() {
    $("button").addClass("animated bounce");

<!-- Only change code above this line -->

<div class="container-fluid">
<h3 class="text-primary text-center">jQuery Playground</h3>
<div class="row">
  <div class="col-xs-6">
    <div class="well" id="left-well">
      <button class="btn btn-default target" id="target1">#target1</button>
      <button class="btn btn-default target" id="target2">#target2</button>
      <button class="btn btn-default target" id="target3">#target3</button>
  <div class="col-xs-6">
    <div class="well" id="right-well">
      <button class="btn btn-default target" id="target4">#target4</button>
      <button class="btn btn-default target" id="target5">#target5</button>
      <button class="btn btn-default target" id="target6">#target6</button>
  **Your browser information:**

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:103.0) Gecko/20100101 Firefox/103.0

Challenge: jQuery - Target HTML Elements with Selectors Using jQuery

Link to the challenge:

It is from Animate.css

The challenge is using an older version so the docs for the current version do not match the class names anymore (migration).