International audienceInterest in gesture-based interaction has been growing considerably, but most systems still limit the recognition of hand gestures to a small set of signs. We present a model for hand gestures that allows the definition of thousands of distinct signals based on the combination of a much smaller number of gesture components. This model comprehends several different kinds of gestures, both static and dynamic and using either hand or both. The choice of types of gestures and individual components is based not only on a review of the relevant literature but also on preliminary user studies, specifically for interaction in virtual and augmented environments and in entertainment and education applications. Gesture recognitio...