A gesture is a series of hand movements with or without finger movements. You can with a gesture show that you open up something, your can signal stop. There are today techniques based on the built in camera in your laptop or the Leap Motion device that can measure your hands and fingers. These techniques can read your gesture.
The Project Virtual Keyboard will give you the opportunity to read gestures with the two devices, one on each hand. The difference versus the other systems is that you can have them with you wherever you go. This is Wearable computing.
Degrees of Freedom
A hand can move up/down, forward/backward, and left/right. We call this that we have three degrees of freedom. Adding the three ways of rotating your hand we have additional three degrees of freedom. Let’s assume that the thumb is only used to operate the single button on the device, then we have four free fingers.
One finger can make a circular motion with its finger tip. That is done by two degrees of freedom for this finger. Four fingers and two degrees of freedom per finger gives us additional eight to the six degrees of freedom for the hand. Now we have fourteen degrees of freedom per hand. Using two hands you have more than you can fully utilize. But who knows there are certainly people that actually can keep all this in mind all the time. Combine this with a music-instrument-application and we will have a one-person-orchestra.