Linear
There are a couple different types of linear progress bars.
Determinate
<div class="progress">
<div class="determinate" style="width: 70%"></div>
</div>
Indeterminate
<div class="progress">
<div class="indeterminate"></div>
</div>
Circular
<div class="preloader-wrapper big active">
<div class="spinner-layer spinner-blue-only">
<div class="circle-clipper left">
<div class="circle"></div>
</div><div class="gap-patch">
<div class="circle"></div>
</div><div class="circle-clipper right">
<div class="circle"></div>
</div>
</div>
</div>
Circular Flashing Colors
<div class="preloader-wrapper big active">
<div class="spinner-layer spinner-blue">
<div class="circle-clipper left">
<div class="circle"></div>
</div><div class="gap-patch">
<div class="circle"></div>
</div><div class="circle-clipper right">
<div class="circle"></div>
</div>
</div>
<div class="spinner-layer spinner-red">
<div class="circle-clipper left">
<div class="circle"></div>
</div><div class="gap-patch">
<div class="circle"></div>
</div><div class="circle-clipper right">
<div class="circle"></div>
</div>
</div>
<div class="spinner-layer spinner-yellow">
<div class="circle-clipper left">
<div class="circle"></div>
</div><div class="gap-patch">
<div class="circle"></div>
</div><div class="circle-clipper right">
<div class="circle"></div>
</div>
</div>
<div class="spinner-layer spinner-green">
<div class="circle-clipper left">
<div class="circle"></div>
</div><div class="gap-patch">
<div class="circle"></div>
</div><div class="circle-clipper right">
<div class="circle"></div>
</div>
</div>
</div>