Bootstrap offers over 250 Glyphicon icons for free. As a thank you, they only ask that you include a link back to Glyphicons whenever possible.
How to use Glyphicons
For performance reasons, all icons require a base class and individual icon class. To use, put code about <span>.
<button type="button" class="btn btn-default" aria-label="Left Align"> <span class="glyphicon glyphicon-align-left" aria-hidden="true"></span> </button> <button type="button" class="btn btn-default btn-lg"> <span class="glyphicon glyphicon-star" aria-hidden="true"></span> Star </button>
Icon classes cannot be directly combined with other components. They should not be used along with other classes on the same element. Instead, add a nested
<span> and apply the icon classes to the
Icon classes should only be used on elements that contain no text content and have no child elements.
There are icons table with the base and individual classes: