A hellabyte (BB) is a unit of measurement for computers of the future. One hellabyte holds 1000 yottabytes (YB) or a octillion (1,000,000,000,000,000,000,000,000,000) bytes. 1000 hellabytes make up 1 geopbyte. A hellabyte is so large that it would take about a trillion supercomputers to store this amount of data.