1) Unit of information 
The zettabit is a multiple of the unit bit for digital information or computer storage. The prefix zetta (symbol Z) is defined in the International System of Units (SI) as a multiplier of 1021 (1 sextillion, short scale), and therefore The zettabit has the unit symbol Zbit or Zb. The zettabit is closely related to the zebibit, a unit multiple deri...