If you don't what variable fonts are it is not a shame because this is a new technology. Variable fonts enables a single font file to behave like multiple fonts. This is done by defining variations (like width and weight) within the font, but the type designer can define many others too.

And this opens up (almost) endless opportunities not just for the font designers but for the frontend developers too for new kinds of responsive typography. The file size savings and fine precision means that many small adjustments could be made to the rendered font, potentially responding dynamically to the reader’s device and environment, as well to the text.

In this session we'll cover:

• Short summary of the thechnology
• New CSS 4 properties to work with font variations
• Demos of the possibilities for fun and for real world usage advantages
• Code examples of the implementations (the easy and the hard parts as well)

• Slides: https://noti.st/thamas/J0wjPB/variable-fonts-in-the-real-world