why is bootstrap jumbotron code example

Example 1: bootstrap jumbotron

<div class="jumbotron">
  <h1 class="display-4">Hello, world!</h1>
  <p class="lead">This is a simple hero unit, a simple jumbotron-style component for calling extra attention to featured content or information.</p>
  <hr class="my-4">
  <p>It uses utility classes for typography and spacing to space content out within the larger container.</p>
  <p class="lead">
    <a class="btn btn-primary btn-lg" href="#" role="button">Learn more</a>
  </p>
</div>

Example 2: jumbotron

<div class="jumbotron jumbotron-fluid">
  <div class="container">
    <h1 class="display-4">Fluid jumbotron</h1>
    <p class="lead">This is a modified jumbotron that occupies the entire horizontal space of its parent.</p>
  </div>
</div>