A Hellabyte is equivalent to 1 x 1027 bytes, or 1,000,000,000,000,000,000,000,000,000 bytes. After an online petition, Google adopted “hella” as a scientific prefix in 2010, and Wolfram Alpha adopted it in 2011.
Usage of the term “hellabyte” has accompanied the advent of big data. We already have words like terabyte, zettabyte and yottabyte to describe large amounts of data, but even those are quickly becoming insufficient.
Brontobyte, Byte, Hard drive terms, Ronna
In 2022, SI (Systems of Units) announced the ronna measurement as the official prefix.