A measurement of digital information storage or transmission, and a multiple of the unit "bit" using the International System of Units prefix.
The Yottabit is 10^24 bits, or 1,000,000,000,000,000,000,000,000 bits or 1000 Zettabits. A Yottabit is equal to 125 Zettabits.
Yottabits have no practical applications as of 2011.
Very similar to yobibits, which use a more exact prefix established by the International Electrotechnical Commission.