Body language is the management of time, space, appearance, posture, gesture, touch, facial expression, eye contact, and voice.

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There are more portable ways to do that, using other kinds of biometric measurements, like eye tracking and facial expression.

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Steady eye contact is the de facto expression of openness in our culture, while avoiding it is a certain sign of discomfort.

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In 20 years, technologies like voice control, eye tracking, facial recognition, and even facial expression recognition will be commonplace and will perform flawlessly.

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