Methods of secretly signaling the right answer to friends are quite varied, ranging from coded sneezes or pencil tapping to high-pitched noises beyond the hearing range of most teachers.
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Students have been known to use more elaborate means, such as using a system of repetitive body signals like hand movements or foot jerking to distribute answers  where a tap of the foot could correspond to answer A, two taps for answer B, and so on.
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Another example of academic dishonesty is a dialogue between students in the same class but in two different time periods, both of which a test is scheduled for that day.
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Student in the earlier time period informs the other student in the later period about the test; that is considered academic dishonesty, even though the first student has not benefitted himself.

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