1. A method for interfacing with a machine using a virtual input device, said method comprising: receiving from an image feed device an image in which a hand is present; detecting fingertips of the hand in said image; classifying said fingertips in a vector signature based on a position of each fingertip with respect to a reference axis defined by the remaining fingertips; comparing said vector signature to pre-stored vector signatures representing known hand states; if the vector signature represents a new state defining a hit state, associating a change of state to a virtual key in a first row of the virtual input device; Sending a function represented by said virtual key to said machine for execution.