The yobibyte  (YiB) is a multiple of the unit byte for digital information.

A yobibyte is a unit of data storage that equals 2 to the 80th power, or 1,208,925,819,614,629,174,706,176 bytes.

A yobibyte is 1,024 zebibytes and is the largest unit of measurement. So, a yottabyte is 1 million exabytes.