Template Content
This is inside a template and won't show without JS activation.
The template tag holds content that won't render until cloned with JavaScript.
This is inside a template and won't show without JS activation.
Template content is hidden above (view source to see it).
The picture element allows multiple image sources for responsive design:
Native HTML5 audio player:
Native HTML5 video player with multiple formats:
Drawing graphics with JavaScript and Canvas API:
The source element is used within picture, audio, and video elements (see examples above).
Einstein's famous equation using MathML:
Why MathML wasn't widely used until recently:
Despite being part of the HTML specification for years, MathML had extremely limited browser support. Internet Explorer never supported it, Chrome dropped support from 2013-2023, and Safari's implementation was incomplete. According to caniuse.com, it wasn't until Chrome 109 (January 2023) that MathML Core gained support in Chromium browsers, finally making it viable for production use. Before this, developers had to rely on JavaScript libraries like MathJax or images for mathematical notation.
This custom element is styled with CSS only:
This is a custom semantic element called "demo-card" that uses only CSS for styling (no JavaScript required).