ion ▁of ▁data ▁consumption , ▁creation ▁and ▁rep lication . ▁In ▁ 2 0 1 5 , ▁ 2 % ▁of ▁total ▁global ▁power ▁was ▁taken ▁up ▁by ▁the ▁Internet ▁and ▁all ▁its ▁components , ▁so ▁energy ▁efficiency ▁with ▁regards ▁to ▁data ▁cent ers ▁has ▁become ▁a ▁central ▁problem ▁in ▁the ▁Z ett aby te ▁Era . ▁ ▁The ▁z ett aby te ▁▁ ▁A ▁z ett aby te ▁is ▁a ▁digital ▁unit ▁of ▁measurement . ▁One ▁z ett aby te ▁is ▁equal ▁to ▁one ▁se xt ill ion ▁bytes ▁or ▁ 1 0 2 1 ▁( 1 , 0 0 0 , 0 0 0 , 0 0 0 , 0 0 0 , 0 0 0 , 0 0 0 , 0 0 0 ) ▁bytes ▁or , ▁one ▁z ett aby te ▁is ▁roughly ▁equal ▁to ▁a ▁tr ill ion ▁gig aby tes . ▁To ▁put ▁this ▁into ▁perspective , ▁consider ▁that ▁" if ▁each ▁ter aby te ▁in ▁a ▁z ett aby te ▁were ▁a ▁kilomet re , ▁it ▁would ▁be ▁equivalent ▁to ▁ 1 , 3 0 0 ▁round ▁tri ps ▁to ▁the ▁moon ▁and ▁back ▁( 7 6 8 , 8 0 0 ▁kilom eters ) ". ▁Or , ▁as ▁former ▁Google ▁CE O ▁Eric ▁Schmidt ▁puts ▁it , ▁from ▁the ▁very ▁beginning ▁of ▁human ity ▁to ▁the ▁year ▁ 2 0 0 3 , ▁an ▁estimated ▁ 5 ▁ex aby tes ▁of ▁information ▁was ▁created , ▁which ▁corresponds ▁to ▁the ▁ 0 . 5 % ▁of