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 hourglass (or sandglass, sand timer, sand watch, or sand clock) is a mechanical device used to measure the passage of time.It comprises two glass bulbs connected vertically by narrow neck that allows a regulated trickle of material (historically sand) from the upper bulb to the lower one.n hourglass (or sandglass, sand timer, sand watch, or sand clock) is a mechanical device used to measure the passage of time.