The document discusses icon fonts and how to implement them. It provides examples of using icon fonts in CSS and HTML, enqueueing icon font stylesheets in WordPress functions.php, and including icon fonts via <link> tags. Popular open source icon fonts like Genericons, Font Awesome, and Elusive Icons are mentioned along with font generators and licensing options. Scalable Vector Graphics (SVG) are also summarized, including benefits like small file sizes and graceful degradation.