Precognition (from the Latin præ-, ""before,"" + cognitio, ""acquiring knowledge""), also called future sight, refers to perception that involves the acquisition of future information that cannot be deduced from presently available and normally acquired sense-based information. The related terms, premonition (from the Latin praemon?re) and presentiment refer to information about future events that is perceived as emotions. The terms are usually used to denote a seemingly parapsychological or extrasensory process of perception, including clairvoyance.