text: How the computer works is that it creates a 3-D computer model of the face that incorporates all 44 major muscles of the human face into the model. Eckman has classfied these six basic emotions into the software: happiness, surprise, anger, disgust, fear, and sadness. (3) Each emotion is associated with characteristic action units to differentiate between emotions. (3) Video imagery (4) is used to capture these action units. For example the text says: "frontalis pars lateralis muscle (above your eyes) raises your eyebrows when youre surprised;..." (3). The computer captures all of that.