The International System of Units has just introduced the term quettabyte, representing one trillion gigabytes.
By the year 2030, the world is expected to generate approximately one sextillion gigabytes (GB) of data annually. The number of DVDs required to store this amount of data would stack from Earth to Mars. This explosive growth of data necessitates a new unit of measurement.
Tahoe Reno 1, Switch’s $3 billion data center, is one of the largest data centers in the world. (Photo: Tech Vision).
Representatives from governments worldwide convened at the General Conference on Weights and Measures (CGPM) on November 18, where they selected the new prefix for the International System of Units (SI), quetta, to describe this immense data volume.
One quetta is equivalent to one trillion, or 10 to the power of 30. One trillion gigabytes is termed a quettabyte.
They also introduced the prefix ronna to represent 10 to the power of 27, along with two other prefixes for extremely small numbers. Ronto denotes 10 to the power of −27, and quecto represents 10 to the power of −30. Earth weighs about one ronnagram, and the mass of an electron is approximately one quectogram.
The last update to the prefix system occurred in 1991 when the prefix yotta was chosen to represent 10 to the power of 24. This update was intended to accommodate advancements in the field of chemistry.
Today, the primary driver is data science, according to Richard Brown, a metrologist at the UK National Physical Laboratory. Brown was the one who proposed the prefix quetta to the CGPM.
Google’s Oregon data center cooling system. The blue pipes carry cold water while the red pipes carry warm water for cooling. (Photo: boredpanda).
With the massive volume of data generated globally each year, people have begun to create their own prefixes for 10 to the power of 27, such as hella or bronto, leading to unofficial terms like hellabyte.
Google’s unit converter indicates that one trillion GB equals one hellabyte. A UK government website refers to it as a brontobyte.
Brown noted that such arbitrary usage can be confusing, as the symbols ‘h’ and ‘b’ for hella and bronto have already been used in the metric system for other units or prefixes. For instance, ‘h’ stands for hecto, indicating a multiple, while ‘H’ represents Henry, a unit of inductance.
To determine new prefixes, Brown searched for words whose abbreviations had never been used as symbols for existing units or prefixes. The new prefixes also needed to align with established precedents.
For example, prefixes indicating large numbers, such as giga or 10 to the power of 9, typically end with ‘a’. Conversely, prefixes describing small numbers, such as atto or 10 to the power of -18, usually end with ‘o’.
Experts further indicate that the SI currently does not require small numbers like ronno or quecto; the purpose of introducing these prefixes is to balance the scale with large numbers.
After quetta, there are no remaining letters in the alphabet to represent new prefixes, so it remains unclear how to select prefixes for numbers larger than 10 to the power of 30, according to Brown.
