Every Data Size Explained, Bit to Quettabyte

Every data size, from the bit to the quettabyte, in the order computers needed them, and the first thing that needed each one. Plus the question on everyone's screen: why does a 1 TB drive say 931 GB? The bit (and why the word wasn't Shannon's), the byte (once one to six bits, and why it ended up eight), the nibble, the kilobyte and the 640K line, the RAMAC's megabytes, the gigabyte, the terabyte, then petabyte, exabyte, zettabyte and yottabyte, and the two newest, the ronnabyte and the quettabyte, voted in at Versailles in 2022. Then the binary twins (kibibyte, mebibyte, gibibyte and on up), who counts which way (Windows, Macs, phones, Linux), and the lawsuits over the gap. Every ladder, window, box and chart on screen is our own drawing. Quotes are typeset from their sources, listed below. Every one, in order 0:00 1 TB says 931? 0:18 Bit 0:52 Byte 1:50 Nibble 2:17 Kilobyte 3:25 Megabyte 4:10 Gigabyte 4:51 Terabyte 5:23 Petabyte 5:47 Exabyte 6:20 Zettabyte 6:59 Yottabyte 7:13 Kibibyte and the binary twins 8:01 Ronnabyte and quettabyte 8:57 Why 1 TB shows 931 GB 10:11 Who counts which way Sources Claude Shannon, A Mathematical Theory of Communication (1948): https://people.math.harvard.edu/~ctm/... Werner Buchholz, his 1977 letter on the byte (ACM): https://amturing.acm.org/Buchholz_102... IBM System/360 Principles of Operation (1964): https://ftp.mirrorservice.org/sites/w... Computer History Museum: first commercial hard disk drive shipped (1956): https://www.computerhistory.org/stora... Hitachi: the first terabyte hard drive (5 January 2007): https://www.hitachi.com/en-us/press/a... BIPM: CGPM 1991, Resolution 4 (zetta, yotta): https://www.bipm.org/en/committees/cg... BIPM: CGPM 2022, Resolution 3 (ronna, quetta): https://www.bipm.org/en/cgpm-2022/res... NIST: prefixes for binary multiples: https://physics.nist.gov/cuu/Units/bi... Cisco: the zettabyte era officially begins (2016): https://blogs.cisco.com/sp/the-zettab... Apple: how storage capacity is measured on Apple devices: https://support.apple.com/en-us/102119 Raymond Chen, The Old New Thing (2009): https://devblogs.microsoft.com/oldnew... Quote Investigator: 640K ought to be enough: https://quoteinvestigator.com/2011/09... Images and credits Tieum512, CC BY 3.0: https://commons.wikimedia.org/wiki/Fi... Don DeBold from San Jose, CA, USA, CC BY 2.0: https://commons.wikimedia.org/wiki/Fi... Marcin Wichary from San Francisco, Calif., CC BY 2.0: https://commons.wikimedia.org/wiki/Fi... the Science Museum, CC BY 4.0: https://commons.wikimedia.org/wiki/Fi... Logg Tandy, CC BY 4.0: https://commons.wikimedia.org/wiki/Fi... ArnoldReinhold, CC BY 2.5: https://commons.wikimedia.org/wiki/Fi... Photos: Wikimedia Commons, Public domain (MIT Photo Service, Deben Dave at English Wikipedia, NASA, U.S. Army Red River Arsenal, NASA Goddard Photo and Video, JMiall, NASA/Apollo 17 crew; taken by either Harrison Schmitt or Ron Evans) Photos: Wikimedia Commons, CC0 (Mramoeba) Newspaper pages, shown where we report what they say: Resolution 4 of the 19th CGPM, 1991. From BIPM, CC BY 4.0. Newspaper pages, shown where we report what they say: NIST, Prefixes for binary multiples, November 1, 2000. From NIST, a US government page. Every ladder, window, drive, box and chart on screen: our own drawing (no maker's screenshot, logo or label) Quotes typeset from their sources, each listed above Library of Congress Main Reading Room: Carol M. Highsmith, Library of Congress, public domain (inside our drawing) U.S. Army Red River Arsenal, public domain #DataSize #Explained #Computers