What exactly is Big Data? This video defines and explains Big Data as well as Hadoop and MapReduce in simple language.
Rating Newest Oldest. Best Answer: Time is an illusion in that it's not a real, *natural* feature of the universe. Time is not absolute, meaning there's no Cosmic Master Clock that ticks off the correct time for the entire universe.
An optical illusion is an illusion caused by the visual system and characterized by a visual percept that appears to differ from reality. Illusions come in a wide variety; their categorization is difficult because the underlying cause is often not clear but a classification proposed by Richard Gregory is useful as an orientation. According to that, there are three main classes: physical, physiological, and cognitive illusions, and in each class there are four kinds: Ambiguities, distortions, par