Check out example codes for "bootstrap progress bar". It will help you in understanding the concepts better.

Code Example 1

<!-- Basic Bootstrap Progress Bar -->
<div class="progress">
  <div class="progress-bar" role="progressbar" aria-valuenow="70"
  aria-valuemin="0" aria-valuemax="100" style="width:70%">
    <span class="sr-only">70% Complete</span>
  </div>
</div>

<!-- W3.CSS-->
<div class="w3-border">
  <div class="w3-grey" style="height:24px;width:20%"></div>
</div>

<!-- Foundation 5.2 (Yep) -->
<div class="progress [small-# large-#] [radius round]">
  <span class="meter [secondary alert success]" style="width: [1 - 100]%"></span>
</div>

<!-- Foundation 6.2 (Yep Yep)-->
<div class="progress" role="progressbar" tabindex="0" aria-valuenow="50" aria-valuemin="0" aria-valuetext="50 percent" aria-valuemax="100">
  <div class="progress-meter" style="width: 50%"></div>
</div>

Code Example 2

<div class="progress">
  <div class="progress-bar" role="progressbar" style="width: 25%;" aria-valuenow="25" aria-valuemin="0" aria-valuemax="100">25%</div>
</div>

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