The term "polygraph" is derived from the Greek, 'poly-graphos,' and literally means "many writings." The name refers to the manner in which targeted physiological activities are simultaneously recorded. The polygraph instrument collects physiological data from several systems in the human body, as questions are asked of the examinee. The data is recorded and displayed in the form of graph tracings, as pictured above. The tracings are then interpreted (scored) by the polygraph examiner.
