Websites will be able to use Force Touch input from Apple’s Force Touch trackpad

The version of Safari that ships with OS X 10.11 ‘El Capitan’ allows web developers to build custom experiences that work with Force Touch input, similar to how native app developers have had access to that new hardware before now. That means that you can set custom actions for how content on your web page responds to deeper clicks on the trackpads that ship in Apple’s newest notebooks

Darrell Etherington | TechCrunch