template carousel - svg+xml

I downloaded the carousel theme and am trying to understand it to make a personal website. There is a ton of css, which much of it I don't understand.

But i'm already stuck at changing the pictures. The carousel theme has responsive images. See a piece of the code. How do i change the picture?

<div class="row featurette">
    <div class="col-md-5">
      <img class="featurette-image img-responsive" data-src="http://holder.js/500x500/auto" alt="Generic placeholder image">
    </div>
    <div class="col-md-7">
      <h2 class="featurette-heading">Oh yeah, it's that good. <span class="text-muted">See for yourself.</span></h2>
      <p class="lead">Donec ullamcorper nulla non metus auctor fringilla. Vestibulum id ligula porta felis euismod semper. Praesent commodo cursus magna, vel scelerisque nisl consectetur. Fusce dapibus, tellus ac cursus commodo.</p>
    </div>
  </div>