This specification defines an API that provides access to the vibration mechanism of the hosting device. Vibration is a form of tactile feedback.
John Smith commented
On desktops, the vibration could be passed into a mouse if it has a force feedback feature built in.
On Xbox, this feature oughta obvious, since the controllers have a vibrationb motor built in.
On other devices, just pass it into the regular vibration motor of the device, if it has one.
Rodney Reid commented
Not only easy, but by implementing this relatively easy API, you'll take us mobile app developers one step closer to not having to write platform specific apps
This seems like an easy API to implement yet would make cross-browser/cross-device compatibility much easier.