The History of Data Storage Measurement
The Bit — The Atom of Information
Claude Shannon, the father of information theory, defined the 'bit' (binary digit) in his 1948 landmark paper 'A Mathematical Theory of Communication'. A bit is the smallest possible unit of information — a 0 or a 1. Shannon showed mathematically that all information — text, images, sound — could be encoded in sequences of bits.
The Byte
Eight bits make a byte — enough to encode one character of text in the ASCII standard. The byte became the fundamental unit of computer storage in the 1950s and 60s. IBM's System/360 in 1964 standardized the 8-bit byte across their mainframe computers, and it became the industry standard.
From Kilobytes to Petabytes
Early computers measured memory in kilobytes (thousands of bytes). The Apollo Guidance Computer that landed humans on the moon in 1969 had just 4 KB of RAM and 72 KB of storage. Today, a modern smartphone has about 256 GB of storage — 64 million times more. The progression from KB to MB to GB to TB to PB has taken less than 60 years.
The Confusion: Binary vs. Decimal
Computer scientists historically used 'kilo' to mean 1,024 (2¹⁰) rather than 1,000, because binary systems work in powers of 2. This means a 'kilobyte' in computing was actually 1,024 bytes — 2.4% more than the metric kilo. In 1998, the IEC introduced new prefixes (kibibyte, mebibyte, gibibyte) to eliminate the confusion, though they haven't fully replaced the old terms.
Storage Today
The total amount of data created, captured, and consumed globally is measured in zettabytes (10²¹ bytes). In 2020, the world generated about 40 zettabytes of data. By 2025, that figure is expected to reach 175 zettabytes. The challenge is no longer creating storage — it's managing, searching, and making sense of the data we already have.