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Timeline of binary prefixes
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This article presents a terminology timeline of binary prefix
Binary prefix
In computing, a binary prefix is a specifier or mnemonic that is prepended to the units of digital information, the bit and the byte, to indicate multiplication by a power of 2...

es. Early computers used two different approaches to memory addressing, representing the address as either a binary number or as a decimal number. Early machines that used decimal addressing included the ENIAC
ENIAC
ENIAC was the first general-purpose electronic computer. It was a Turing-complete digital computer capable of being reprogrammed to solve a full range of computing problems....

, UNIVAC 1, IBM 702
IBM 702
The IBM 702 was IBM's response to the UNIVAC—the first mainframe computer using magnetic tapes. Because these machines had less computational power than the IBM 701 and ERA 1103, which were favored for scientific computing, the 702 was aimed at business computing.The system used electrostatic...

, IBM 705, IBM 650
IBM 650
The IBM 650 was one of IBM’s early computers, and the world’s first mass-produced computer. It was announced in 1953, and over 2000 systems were produced between the first shipment in 1954 and its final manufacture in 1962...

, IBM 1400 series
IBM 1400 series
The IBM 1400 series were second generation mid-range business decimal computers that IBM sold in the early 1960s. They could be operated as an independent system, in conjunction with IBM punched card equipment, or as auxiliary equipment to other computer systems.1400-series machines stored...

, and IBM 1620
IBM 1620
The IBM 1620 was announced by IBM on October 21, 1959, and marketed as an inexpensive "scientific computer". After a total production of about two thousand machines, it was withdrawn on November 19, 1970...

. Early binary addressed computers included Zuse Z3, Colossus
Colossus computer
Not to be confused with the fictional computer of the same name in the movie Colossus: The Forbin Project.Colossus was the world's first electronic, digital, programmable computer. Colossus and its successors were used by British codebreakers to help read encrypted German messages during World War II...

, Whirlwind
Whirlwind (computer)
The Whirlwind computer was developed at the Massachusetts Institute of Technology. It is the first computer that operated in real time, used video displays for output, and the first that was not simply an electronic replacement of older mechanical systems...

, AN/FSQ-7
AN/FSQ-7
The AN/FSQ-7 was a computer model developed and built in the 1950s by IBM in partnership with the US Air Force. Fifty-two were built and used for command and control functions for the Semi Automatic Ground Environment air-defense system...

, IBM 701
IBM 701
The IBM 701, known as the Defense Calculator while in development, was announced to the public on April 29, 1952, and was IBM’s first commercial scientific computer...

, IBM 704
IBM 704
The IBM 704, the first mass-produced computer with floating point arithmetic hardware, was introduced by IBM in 1954. The 704 was significantly improved over the IBM 701 in terms of architecture as well as implementations which were not compatible with its predecessor.Changes from the 701 included...

, IBM 709
IBM 709
The IBM 709 was an early computer system introduced by IBM in August, 1958. It was an improved version of the IBM 704 and the second member of the IBM 700/7000 series of scientific computers....

, IBM 7030
IBM 7030
The IBM 7030, also known as Stretch, was IBM's first transistorized supercomputer. The first one was delivered to Los Alamos National Laboratory in 1961....

, IBM 7090
IBM 7090
The IBM 7090 was a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computers and was designed for "large-scale scientific and technological applications". The 7090 was the third member of the IBM 700/7000 series scientific computers. The first 7090 installation...

, IBM 7040
IBM 7040
The IBM 7040 was a historic but short-lived model of transistor computer built in the 1960s.It was announced by IBM in December 1961, but did not ship until April, 1963. A later member of the IBM 700/7000 series of scientific computers, it was a scaled down version of the IBM 7090. It was not fully...

, IBM System/360 and DEC PDP series
Programmed Data Processor
Programmed Data Processor was the name of a series of minicomputers made by Digital Equipment Corporation. The name 'PDP' intentionally avoided the use of the term 'computer' because, at the time of the first PDPs, computers had a reputation of being large, complicated, and expensive machines, and...

. Decimal machines typically had memory configured in even decimal multiples (e.g., blocks of 100 and later 1000) and the abbreviation K or k, if it was used, had is normal meaning of 1000. Binary machine memory came in powers of two or small multiples of powers of two. In this context K or k was sometimes used to denote multiples of 1024 units or just the approximate size (e.g., '65K' for 65536 (216)). Early digital telephony established a standard of 8000 ('8K') samples per second. This timeline lists early examples of these usages.

1940s
1940s
File:1940s decade montage.png|Above title bar: events which happened during World War II : From left to right: Troops in an LCVP landing craft approaching "Omaha" Beach on "D-Day"; Adolf Hitler visits Paris, soon after the Battle of France; The Holocaust occurred during the war as Nazi Germany...

1943–1944
  • J.W. Tukey
    John Tukey
    John Wilder Tukey ForMemRS was an American statistician.- Biography :Tukey was born in New Bedford, Massachusetts in 1915, and obtained a B.A. in 1936 and M.Sc. in 1937, in chemistry, from Brown University, before moving to Princeton University where he received a Ph.D...

     coins the word bit as an abbreviation of "binary digit".

1947
  • "The Whirlwind I Computer is being planned for a storage capacity of 2,048 numbers of 16 binary digits each."

1948
  • Reference to Tukey's "bit" is made in a paper by information theorist Claude Shannon.

1950s
1950s
The 1950s or The Fifties was the decade that began on January 1, 1950 and ended on December 31, 1959. The decade was the sixth decade of the 20th century...

  • In the 1950s, "1 kilobit" meant "1000 bits":
    • "In the '50s, amazingly enough---and only total coincidence---I actually was given the job of writing the operational specifications […] They handed me this thing and said, "You're going to define how the hand-over process works between direction centers," and---and I had no idea what they were talking about. But we had... uh... one-kilobit lines connecting the direction centers and I thought, "Good God! 1,000 bits a second. Well, we’ll surely be able to figure out something to do with that." — Saverah Warenstein


1952
  • The first magnetic core memory, from the IBM 405 Alphabetical Accounting Machine, is tested successfully in April 1952. (The image shows 10×12 cores; presumably one of 8)
    • "Teaming up with a more experienced engineer, [Mike Haynes] built a core memory with just enough capacity to store all the information in an IBM punched card: 960 bits in an 80×12 array. In May 1952 it was successfully tested as a data buffer between a Type 405 alphabetical accounting machine and a Type 517 summary punch. This first functional test of a ferrite core memory was made in the same month that a four-times smaller 16×16-bit ferrite core array was successfully tested at MIT."
  • The IBM 701
    IBM 701
    The IBM 701, known as the Defense Calculator while in development, was announced to the public on April 29, 1952, and was IBM’s first commercial scientific computer...

    , a binary addressed computer containing 72 Williams tube
    Williams tube
    The Williams tube or the Williams-Kilburn tube , developed in about 1946 or 1947, was a cathode ray tube used to electronically store binary data....

    s of 1024 bits each, is released in April.
    • Principles of Operation does not seem to use "kilobit" anywhere. Specifies that memory tubes (IBM 706) hold 1024 bits each, drum memories (IBM 731) hold 2048 words each.
    • The IBM 737 optional magnetic core storage stores 4,096 words. Each plane stored 16×16 = 4,096 bits.


1955
  • The IBM 704
    IBM 704
    The IBM 704, the first mass-produced computer with floating point arithmetic hardware, was introduced by IBM in 1954. The 704 was significantly improved over the IBM 701 in terms of architecture as well as implementations which were not compatible with its predecessor.Changes from the 701 included...

     (a binary machine) manual uses decimal arithmetic for powers of two, without prefixes
    • "Magnetic core storage units are available with capacities of either 4,096 or 32,768 core storage registers; or two magnetic core storage units, each with a capacity of 4,096 core storage registers, may be used. Thus, magnetic core storage units are available to give the calculator a capacity of 4,096, 8,192, or 32,768 core storage registers."
    • "Each drum has a storage capacity of 2048 words."


1956
February
  • The IBM 702
    IBM 702
    The IBM 702 was IBM's response to the UNIVAC—the first mainframe computer using magnetic tapes. Because these machines had less computational power than the IBM 701 and ERA 1103, which were favored for scientific computing, the 702 was aimed at business computing.The system used electrostatic...

     (a decimal addressed machine) Preliminary Manual of Information uses decimal arithmetic for powers of ten, without prefixes.
    • "Electrostatic memory is the principal storage medium within the machine. It consists of cathode ray tubes which can store up to 10,000 characters of information in the form of electrostatic charges.... Additional storage, as required, may be provided through the use of magnetic drum storage units, each having a capacity of 60,000 characters."
    • "A character may be a letter of the alphabet, a decimal number, or any of eleven different punctuation marks or symbols used in report printing."
    • "Each one of the 10,000 positions of memory is numbered from 0000 to 9999 and each stored character must occupy one of these positions." (page 8)
July
  • The word byte is coined by Dr. Werner Buchholz
    Werner Buchholz
    Werner Buchholz is a noted American computer scientist. In July 1956, he coined the term byte, a unit of digital information to describe an ordered group of bits, as the smallest amount of data that a computer could process .As a member of the team at International Business Machines that designed...

     in July 1956, during the early design phase for the IBM Stretch
    IBM 7030
    The IBM 7030, also known as Stretch, was IBM's first transistorized supercomputer. The first one was delivered to Los Alamos National Laboratory in 1961....

     computer.
  • IBM 650 RAMAC (a decimal addressed machine) announcement
    • "The 650 RAMAC combines the IBM 650 Magnetic Drum Data Processing Machine with a series of disk memory units which are capable of storing a total of 24-million digits. The 305 RAMAC is an entirely new machine which contains its own input and output devices and processing unit as well as a built-in 5-million-digit disk memory."


1957
June
  • The IBM 705 (a decimal addressed machine) Operating manual uses decimal arithmetic for powers of ten, without prefixes.
    • "A total of 40,000 characters can be stored within the main storage unit of the Type 705."
    • "Each one of the 40,000 positions in memory is numbered from 0000 to 39,999." (page 17)
    • "One or more magnetic drums are available as optional equipment with a capacity of 60,000 characters each."

  • Lewis, W.D., Coordinated broadband mobile telephone system
    • Earliest instance of "kilobit" in both IEEE explore and Google Scholar: "Central controls the mobile link with a rate of 20 kilobits per second, or less".


1959
  • The term 32k is used in print to refer to a memory size of 32768 (215).

} The author is with the Westinghouse Electric Corporation.

1960s
1960s
The 1960s was the decade that started on January 1, 1960, and ended on December 31, 1969. It was the seventh decade of the 20th century.The 1960s term also refers to an era more often called The Sixties, denoting the complex of inter-related cultural and political trends across the globe...

1960
May Frequency Diversity Communications System is filed on May 13, 1960:
    • "In actual construction, the delay line, which provides a total delay from one end to the other of one baud
      Baud
      In telecommunications and electronics, baud is synonymous to symbols per second or pulses per second. It is the unit of symbol rate, also known as baud rate or modulation rate; the number of distinct symbol changes made to the transmission medium per second in a digitally modulated signal or a...

       (10 microseconds for a 100 kilobit per second information rate), may be fabricated from lumped parameter elements, i.e., inductors and capacitors, in a well-known manner."
    • "At a 100 kilobit per second information rate, both mark and space signals will generally be transmitted in any 0.0001 sec, interval, and therefore this requirement is easily met with conventional resistors and capacitors."
October
    • The 8K core stores were getting fairly common in this country in 1954. The 32K store started mass production in 1956; it is the standard now for large machines and at least 200 machines of the size (or its equivalent in the character addressable machines) are in existence today (and at least 100 were in existence in mid-1959).


1955–1961
  • A search of the Computer History Museum's Stretch collection of 931 text documents dated from September 1955 through September 1961 shows no usage of k or K to describe main storage size.


1961
    • Quoted in OED as first instance of "kilobit", though "it is more usual" suggests it is already in common use (see timeline entry for 1957)
February 17
  • Described device contains 512 words, 24 bits each (=12,288 bits)
September
  • "It is no longer reasonable to spend as much time to transmit an 80 bit address as 12 kilobits of message information-a 1500 to 1 ratio.... We have theoretically and experimentally proved that speech can be compressed from the straightforward requirement for 48 kilobit PCM channel capability to 2400 bits by the application of the Dudley syllabic vocoder."

October
  • The IBM 7090
    IBM 7090
    The IBM 7090 was a second-generation transistorized version of the earlier IBM 709 vacuum tube mainframe computers and was designed for "large-scale scientific and technological applications". The 7090 was the third member of the IBM 700/7000 series scientific computers. The first 7090 installation...

     Data Processing System (a binary machine), Additional Core Storage (65K means "approximately 65000")
    • "The Additional Core Storage feature for the IBM 7090 Data Processing System provides a second IBM 7302 Core Storage, increasing the capacity of main storage by 32,768 words. The block of storage represented by both 7302 units is referred to as "main storage unit."
    • "Additional core storage provides two methods of using main storage: (1) The 65K mode—the computer program is enabled to address both of the main storage units, and (2) the 32K mode—the computer program is able to address only one storage unit, so that main storage capacity available to that program is effectively 32,768 words."
  • The IBM 1410
    IBM 1410
    The IBM 1410, a member of the IBM 1400 series, was a variable wordlength decimal computer that was announced by IBM on September 12, 1960 and marketed as a midrange "Business Computer". It was withdrawn on March 30, 1970. The 1410 was similar in design to the very popular IBM 1401, but it had one...

     Data Processing System, which used modified decimal addressing, uses decimal arithmetic for powers of ten, without prefixes
    • "Core storage units are available in 10,000-, 20,000- or 40,000-character position capacities."
    • "The matrix switch makes it possible to address any one of the 100 X-drive lines (in a 10K core array)."
    • "The 40K core array requires 40,000 valid five-position addresses from 0,000 to 39,999."
    • "This operation check detects errors in programming that cause invalid addresses. Examples: 40,000-and-above on a 40K core array; 20,000-and-above on a 20K core array. On a 10K core array, invalid addresses are detected by the address-bus validity check."


1962
  • A reference to a "4k IBM 1401" meant 4,000 characters of storage (memory).


1963
August
  • Ludwig uses kilobit in the decimal sense
  • DEC
    Digital Equipment Corporation
    Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

     Serial Drum Type 24
    • "Drums are equipped to store either 64, 128, or 256 data blocks, providing a memory capability of 16384, 32768, or 65536 computer words" (no abbreviations)

November
  • Honeywell
    Honeywell
    Honeywell International, Inc. is a major conglomerate company that produces a variety of consumer products, engineering services, and aerospace systems for a wide variety of customers, from private consumers to major corporations and governments....

     200 Summary Description
    • "The main memory is a magnetic core ... The memory unit supplied as part of the basic central processor has a capacity of 2,048 characters, each of which is stored in a separate, addressable, memory location. This capacity may be expanded in modular increments by adding one 2,048-character module and additional 4,096-character modules."
    • "Random access disc file and control (disc capacities of up to 100 million characters are available.)"
    • "Up to eight drum storage units can be connected to the Model 270 Random Access Drum Control. Each drum provides storage for 2,621,441 characters, allowing a total capacity of approximately 21 million characters."


1964
  • Gene Amdahl's
    Gene Amdahl
    Gene Myron Amdahl is a Norwegian-American computer architect and high-tech entrepreneur, chiefly known for his work on mainframe computers at IBM and later his own companies, especially Amdahl Corporation...

     seminal April 1964 article on IBM System/360 used 1K to mean 1024.
  • Leng, Gordon Bell
    Gordon Bell
    C. Gordon Bell is an American computer engineer and manager. An early employee of Digital Equipment Corporation 1960–1966, Bell designed several of their PDP machines and later became Vice President of Engineering 1972-1983, overseeing the development of the VAX...

    , et al., use K in the binary sense:
"The computer has two blocks of 4K, 18-bit words of memory, (1K=1024 words), attached to its central processor"

    • IBM Data Processing Division press release distributed on April 7, 1964.
      • "System/360 core storage memory capacity ranges from 8,000 characters of information to more than 8,000,000."
    • IBM 7090/7094 Support Package for IBM System/360 - November
      • "An IBM 1401 Data Processing System with the following minimum configuration is also required: 1. 4K positions of core storage" - ADDRESS SELECTION CONTROL APPARATUS - Filed April 6, 1964
      • 'To facilitate understanding of the invention, the main storage area has been illustrated as being of 8K capacity; however, it is to be understood that the main storage area may be of larger capacity (e.g., 16K, 32K or 64K) by storing address selection control data in bit positions "2," "1" and "0" of M register 197, respectively.'


    1965
    • "Each IBM 2315 disk cartridge can hold the equivalent of more than one million characters of information." IBM 1130 Press Release, February 11, 1965 "One method of designing a slave memory for instructions is as follows. Suppose that the main memory has 64K words (where K=1024) and, therefore, 16 address bits, and that the slave memory has 32 words and, therefore, 5 address bits."
    • IBM 1620
      IBM 1620
      The IBM 1620 was announced by IBM on October 21, 1959, and marketed as an inexpensive "scientific computer". After a total production of about two thousand machines, it was withdrawn on November 19, 1970...

       CPU Model 1 (a decimal machine) System Reference Library, dated 7/19/65, states:
      • "A core storage module, which is 20,000 addressable positions of magnetic core storage, is located in the 1620. Two additional modules are available ... Each core storage module (20,000 positions) is made up of 12 core planes as shown in Figure 3. Each core plane contains all cores for a specific bit value."


    1966 CONTIGUOUS BULK STORAGE ADDRESSING is filed on Jan 3, 1966
      • 'Note that "K" as used herein indicates "thousands." Each storage location in the present embodiment includes 64 data bits and 8 related parity bits, as described herein.'
      • "Thus, if only storage unit 1A were provided, it would contain addresses 0 through 32K; storage IB would include addresses between 32K and 64K, storage 2A would contain addresses between 64K and 96K, ..."


    1968
    • A Univac 9400 disc based computer system ... "can have 2-8 8411 drives for 14.5-58 megabytes capacity. The 8411 has a transfer rate of 156K bytes per second." using megabytes in a decimal sense

    March
    • Donald Morrison proposes to use the Greek letter kappa (κ) to denote 1024 bytes, κ2 to denote 1024×1024, and so on.

    name="Morrison"> (At the time, memory size was small, and only K was in widespread use.)
    June
    • Wallace Givens
      Wallace Givens
      James Wallace Givens, Jr. was a mathematician and a pioneer in computer science. He is the eponym of the well-known Givens rotations...

       responded with a proposal to use bK as an abbreviation for 1024 and bK2 or bK2 for 1024×1024, though he noted that neither the Greek letter nor lowercase letter b would be easy to reproduce on computer printers of the day.
    October
    • Bruce A. Martin further proposed that the prefixes be abandoned altogether, and the letter B be used as a binary exponent, similar to E notation, to create shorthands like 3B20 for 3×220 = 3 MiB

    name="Martin">

    1969
    • IBM 1401
      IBM 1401
      The IBM 1401 was a variable wordlength decimal computer that was announced by IBM on October 5, 1959. The first member of the highly successful IBM 1400 series, it was aimed at replacing electromechanical unit record equipment for processing data stored on punched cards...

       (a decimal machine) Simulator for IBM
      IBM
      International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

       OS/360
      • "1401 features supported are advanced programming, sense switches, tapes, multiply, divide, 16K core, and all standard instructions except Select Stacker."
      • "1401 core is simulated by 16,000 bytes of S/360 core obtained dynamically."
      • "Enough core must be available to allow at least 70K for a problem program area. If tape simulation is not required, this core requirement may be reduced to 50K with the removal of the tape Buffer area." HIGH DENSITY PERMANENT DATA STORAGE AND RETRIEVAL SYSTEM is filed on March 17, 1969 earliest Google Patent search containing "kilobyte")
      • "The data word processor 606 handles the inflow and out-flow of byte-oriented input/output data and interleaved signals at a rate of, for example, 500 kilobytes per second. Instruction processing rates of four to eight per microsecond are required for such a data flow." Memory Control System is filed on Oct 29, 1969
      • "FIG. 2a shows a practical example of an operand address which consists of, for example 24 bits. It is assumed herein that each block includes 32 bytes, each sector includes 1 kilobyte, the buffer memory 116 includes 4 kilobytes, and read data is represented by one double word or 64 bits, as one word in this case consists of 32 bits."
    • IBM System/360 Component Descriptions (IBM 2314 Direct Access Storage Facility)
      • "Each module can store 29.17 million bytes or 58.35 million packed decimal digits ... total on-line storage capacity is 233.4 million bytes"
    • "Each 11-disc pack (20 surfaces) has a storage capacity of 29 megabytes; maximum storage capacity with the largest version using a ninth drive as a spare) is 233,400,000 bytes."
    • DEC
      Digital Equipment Corporation
      Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

       PDP-11
      PDP-11
      The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...

       (a binary addressed machine) Handbook
      • "PDP-11 addressing modes include . . . and direct addressing to 32K words" (Page 2) This appears to be the only use of K in this manual, though; elsewhere sizes are spelled out in full. Contrast the 1973 PDP-11/40 Manual, which defines K as 1024. (Below)
    • "... each removable disc has a capacity of 2.3 million bytes or 3.07 million 6-bit characters. Up to four drives can be attached to a single controller, resulting in a total storage capacity of 9.2 megabytes." Usage of million and mega in decimal sense to describe HDD.

    1970s
    1970s
    File:1970s decade montage.png|From left, clockwise: US President Richard Nixon doing the V for Victory sign after his resignation from office after the Watergate scandal in 1974; Refugees aboard a US naval boat after the Fall of Saigon, leading to the end of the Vietnam War in 1975; The 1973 oil...

    1970
    • "The following are excerpts from an IBM Data Processing Division press technical fact sheet distributed on June 30, 1970.
      • Users of the Model 165 will have a choice of five main core storage sizes, ranging from 512,000 to over 3-million bytes. Seven main memory sizes are available for the Model 155, ranging from 256,000 to over 2-million bytes." "Each of the five system/360 model 75 computers (Fig. 2) has one megabyte of primary core storage plus four megabytes of large core storage (LCS, IBM 2361)."

    1971
    • IBM System/360 Operating System: Storage Estimates uses K in a binary sense approximately 450 times, such as ""System/360 Configuration: Model 40 with 64K bytes of storage and storage protection." Note the letter "K" is also sometimes used as a variable in this document (see page 23).


    1972
    September
    • Lin and Mattson introduce the term Mbyte.

    }

    1973.
      • OCEANPORT, N.J., SEPT. 25, 1973 -- A 16-bit minicomputer priced at under $2,000.00 in quantities and a 32-bit minicomputer priced at under $6,000.00 in quantities were introduced today by Interdata, Inc. The 16-bit mini, the Model 7/16, includes an 8KB memory unit in its basic configuration, and will be available for delivery in the first quarter of 1974. The single unit price of the 7/16 is $3,200.00. The 32-bit mini, the Model 7/32, includes a 32KB memory unit and will be available for delivery in the second quarter of 1974. The single unit price of the 7/32 is $9,950.00.
    • DEC
      Digital Equipment Corporation
      Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

       PDP-11/40 Manual
      • "Direct addressing of 32K 16-bit words or 64K 8-bit bytes (K = 1024)" (Page 1-1) Contrast the 1969 PDP-11 Handbook, which avoids this usage almost everywhere. (Above)


    1974
    • The seminal 1974 Winchester HDD article which makes extensive use of Mbytes with M being used in the conventional, 106 sense. Arguably all of today's HDD's derive from this technology.
    • The October 1974 CDC
      Control Data Corporation
      Control Data Corporation was a supercomputer firm. For most of the 1960s, it built the fastest computers in the world by far, only losing that crown in the 1970s after Seymour Cray left the company to found Cray Research, Inc....

       Product Line Card unambiguously uses MB to characterize HDD capacity in millions of bytes.


    1975
    • Byte Magazine
      Byte (magazine)
      BYTE magazine was a microcomputer magazine, influential in the late 1970s and throughout the 1980s because of its wide-ranging editorial coverage...

       Dec 1975 article on IBM 5100 includes the following:
      • "User memory starts at 16K bytes in the minimum configuration and can be expanded to 64K bytes (65,536)."
    • Gordon Bell
      Gordon Bell
      C. Gordon Bell is an American computer engineer and manager. An early employee of Digital Equipment Corporation 1960–1966, Bell designed several of their PDP machines and later became Vice President of Engineering 1972-1983, overseeing the development of the VAX...

       uses the term megabytes:

    }

    1976
    • DEC RK05/RK05J/RK05F disk drive maintenance manual
      • "Bit Capacities (unformatted)" "25 million" | "50 million" (57,600 bits/ track * 406 | 812 tracks = 23,385,600 | 46,771,200 bits)
    • The Memorex 1976 annual report has 10 instances of the use of megabyte to describe storage devices and media.
    • Caleus Model 206-306 Maintenance Manual uses 3MB to characterize a drive having 3,060,000 bytes capacity.
    • The first 5¼ inch floppy disk drive, the Shugart SA 400, is introduced in August 1976. The drive had 35 tracks and was single sided. The data sheet gives the unformatted capacity as 3125 bytes per track for a total of 109.4 Kbytes (3125 × 35 = 109,375). When formatted with 256 byte sectors and 10 sectors per track the capacity is 89.6 Kbytes (256 × 10 × 35 = 89,600).


    1977
    • HP 7905A Disc Drive Operator's Manual
      • "nearly 15 million bytes" with no other abbreviations

    • 1977 Disk/Trend Report - Rigid Disk Drives, published June 1977
      • This first edition of the annual report on the hard disk drive industry makes extensive use of MB as 106 bytes. The industry, in 1977, is segmented into nine segments ranging from "Disk Cartridge Drives, up to 12 MB" to "Fixed Disk Drives, over 200 MB." While the categories changed during the next 22 years of publication, Disk/Trend, the principal marketing study of the hard disk drive industry always and consistently categorized the industry in segments using prefixes M and later G in the decimal sense.

    • VAX11/780 Architecture Handbook 1977-78. Copyright 1977 Digital Equipment Corporation.
      • Page 2-1 "physical address space of 1 gigabyte (30 bits of address)" The initial hardware was limited to 2 M bytes of memory utilizing the 4K MOS RAM chips. The VAX11/780 handbooks use M byte and Mbyte in the same paragraph.


    1978
    • DEC
      Digital Equipment Corporation
      Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

       RM02/03 Adapter Technical Description Manual
      • "The RM02 or RM03 Disk Drive (Figure 1-1) is an 80M byte (unformatted; 67M byte formatted) … storage device … in the 16-bit format, the maximum storage capacity is 33,710,080 data words per disk pack" (33,710,080 * 16/8 = 67,420,160 8-bit bytes)


    1979
    • Fujitsu
      Fujitsu
      is a Japanese multinational information technology equipment and services company headquartered in Tokyo, Japan. It is the world's third-largest IT services provider measured by revenues....

       M228X Manual
      • "Storage capacity (unformatted)" "67.4 MB", "84.2 MB", etc.
      • "20,480 Bytes" per track, 4 tracks per cylinder, 808+15 cylinders = 67,420,160 bytes

    • Sperry
      Sperry Corporation
      Sperry Corporation was a major American equipment and electronics company whose existence spanned more than seven decades of the twentieth century...

       Univac
      UNIVAC
      UNIVAC is the name of a business unit and division of the Remington Rand company formed by the 1950 purchase of the Eckert-Mauchly Computer Corporation, founded four years earlier by ENIAC inventors J. Presper Eckert and John Mauchly, and the associated line of computers which continues to this day...

       Series V77 Microcomputer Systems Brochure, Circa 1978, Printed July 1979
      • Page 5: Table list memory options as 64KB, 128KB, and 256KB. Memory Expansion is up to 2048KB
      • Page 9: "Memory for the V77-800 is available in 128K byte and 256K byte increments up to a maximum of 2 megabytes "
      • Page 21: Moving Head Disks - units up to 232 million byte disk pack systems. Diskette - storage of 0.5 MB per drive.

    • The following statistics were taken from the Dec 1979 editions of Byte Magazine and Datamation. The first number is the number of articles or advertisements that used any variant of megabyte for HDDs or Main memory while the second number is the total number of times it was used in the advertisement or article.
    {| class="wikitable"

    |-
    ! Variant
    ! Used In Decimal Sense
    ! Used In Binary Sense
    |-
    | million || 1 / 1 ||
    |-
    | megabyte || 9 / 12 || 1 / 1
    |-
    | MByte or M Byte || 3 /10 ||
    |-
    | MB || 5 / 18 ||
    |-
    | Mb || 2 / 2 || 1 / 3
    |-
    | M || 1 / 1 ||
    |-
    | Total || 20 / 43 || 2 / 4
    |}

    1980s
    1980s
    File:1980s decade montage.png|thumb|400px|From left, clockwise: The first Space Shuttle, Columbia, lifted off in 1981; American President Ronald Reagan and Soviet leader Mikhail Gorbachev eased tensions between the two superpowers, leading to the end of the Cold War; The Fall of the Berlin Wall in...

    1980
    • Shugart Associates
      Shugart Associates
      Shugart Associates was a computer peripheral manufacturer that dominated the floppy disk drive market in the late 1970s and is famous for introducing the 5¼-inch minifloppy disk drive....

       Product Brochure, published Jun 1980 specifies the capacity of its two HDDs using megabytes and MB in a decimal sense, e.g. SA1000 formatted capacity is stated as "8.4 MB" and is actually 256×32×1024 = 8,388,608 bytes.
    • Shugart Associates SA410/460 Data Sheet published Oct 1980 contains capacity specifications as follows:
    {| class="wikitable"

    |-
    ! Formatted Capacity
    ! SA410
    Single/Double Density
    ! SA460
    Single/Double Density
    |-
    | Per Disk
    | 204.8/409.6 KBytes
    | 409.6/819.2 KBytes
    |-
    | Per Surface
    | 204.8/409.6 KBytes
    | 204.8/409.6 KBytes
    |-
    | Per Track
    | 2.56/5.12 KBytes
    | 2.56/5.12 KBytes
    |-
    | Sectors/Track
    | 10
    | 10
    |}
    • Shugart Associates was one of the companies that invented the 5¼" FD using K in a decimal sense.
    • Note that the same data sheet uses MByte in a decimal sense.


    1981
    • 8086
      Intel 8086
      The 8086 is a 16-bit microprocessor chip designed by Intel between early 1976 and mid-1978, when it was released. The 8086 gave rise to the x86 architecture of Intel's future processors...

       Object Module Formats
      • "The 8086 MAS is 1 megabyte (1,048,576)"

    • Quantum
      Quantum Corp.
      Quantum Corporation is a manufacturer of tape drive, tape automation, data deduplication storage products and scalable file storage software, based in San Jose, California...

       Q2000 8" Media Fixed Disk Drive Service Manual
      • "four models ... the Q2010 having an unformatted 10.66 Mb capacity on one disk platter and two heads, the ... 21.33 Mb ... 32.00 Mb ... 42.66 Mb"
      • (1024 tracks × "10.40Kb" per track = 10649 "Kb", which they write as "10.66Mb", so 1 "Mb" = 1000 "Kb")
      • (256 Bytes per sector, 32 Sectors/tk = 8192 bytes, which they write as "8.20Kb" per track)
      • "Storage capacity of 10, 20, 30, or 40 megabytes"
      • "4.34M bits/second transfer rate"

    • Apple Disk III data sheet
      • "Formatted Data Capacity: 140K bytes"
      • Apple uses K is a binary sense since the actual formatted capacity is 35 tracks * 16 Sectors * 256 bytes = 140 KiB = 143.360 kB


    1982
    • Brochure for the IBM Personal Computer (PC)
      • "User memory: 16KB to more than 512KB", "single-sided 160KB or double-sided 320KB diskette drives"

    "The drives are soft sectored, single or double sided, with 40 tracks per side. They are Modified Frequency Modulation (MFM) coded in 512 byte sectors, giving a formatted capacity of 163,840 bytes per drive for single sided and 327,680 bytes per drive for double sided."

    • Seagate
      Seagate Technology
      Seagate Technology is one of the world's largest manufacturers of hard disk drives. Incorporated in 1978 as Shugart Technology, Seagate is currently incorporated in Dublin, Ireland and has its principal executive offices in Scotts Valley, California, United States.-1970s:On November 1, 1979...

       ST 506/412 OEM Manual
      • "Total formatted capacity ... is 5/10 megabytes (32 sectors per track, 256 bytes per sector, 612/1224 tracks)"


    1983
    • IBM
      IBM
      International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

       S/360 S/370 Principles Of Operation GA22-7000 includes as statement:
      • "In this publication, the letters K, M and G denote the multipliers 210, 220 and 230 respectively. Although the letters are borrowed from the decimal system and stand for kilo 103, mega 106 and giga 109 they do not have decimal meaning but instead present the power of 2 closest to the corresponding power of 10."
    • IBM 341 4-inch Diskette Drive
      • unformatted capacity "358,087 bytes"
      • "Total unformatted capacity (in kilobytes): 358.0"
    • Maxtor
      Maxtor
      Maxtor Corporation, founded in 1982 and acquired by Seagate Technology in 2006, was an American manufacturer of computer hard disk drives, the third largest in the world immediately prior to acquisition...

       XT-1000 brochure
      • "Capacity, unformatted" 9.57 MB per surface = 10,416 bytes per track * 918 tracks per surface = 9,561,888 byte (decimal MB)
    • Shugart Associates
      Shugart Associates
      Shugart Associates was a computer peripheral manufacturer that dominated the floppy disk drive market in the late 1970s and is famous for introducing the 5¼-inch minifloppy disk drive....

       SA300/350 Data Sheet published circa Nov 1983 (one of the first MIC standard 3.5" FDDs) contains capacity specifications as follows:
    {| class="wikitable"

    |-
    ! Formatted Capacity
    ! Single Sided
    Single/Double Density
    ! Double Sided
    Single/Double Density
    |-
    | Per Disk
    | 204.8/409.6 kbytes
    | 409.6/819.2 kbytes
    |-
    | Per Surface
    | 204.8/409.6 kbytes
    | 204.8/409.6 kbytes
    |-
    | Per Track
    | 2.56/5.12 kbytes
    | 2.56/5.12 kbytes
    |-
    | Sectors/Track
    | 10
    | 10
    |}
    Shugart Associates, one of the leading FD companies used k in a decimal sense.


    1984
    The Macintosh Operating System
    Mac OS
    Mac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...

     is the earliest known operating system using the prefix K in a binary sense to report memory size and HDD capacity    .
    In the original 1984 Apple Macintosh ad, page 8, Apple characterized its 3½ floppy disk as "400K," that is, 800×512 byte sectors or 409,600 bytes = 400 KiB. Similarly, the February 1984 Byte Magazine
    Byte (magazine)
    BYTE magazine was a microcomputer magazine, influential in the late 1970s and throughout the 1980s because of its wide-ranging editorial coverage...

     review describes the FD as "400K bytes".


    1985
    September 1985. Apple introduced Macintosh Finder 5.0 with HFS (Hierarchical File System)along with the Mac's first hard drive, the Hard Disk 20. Finder 5.x displayed drive capacity in binary K units. The Hard Disk 20 Manual specifies the HDD as having
    "Data capacity (formatted): 20,769,280 bytes
    Bytes per block: 532 (512 user data, 20 system data)
    Total disk blocks: 39,040
    and has the following definition in its glossary:

    Note the user data is 39,040 * 512 = 19,988,480 bytes.


    1986
    Apple IIgs
    Apple IIGS
    The Apple , the fifth and most powerful model in the Apple II series of personal computers produced by Apple Computer. The "GS" in the name stands for Graphics and Sound, referring to its enhanced graphics and sound capabilities, both of which greatly surpassed previous models of the line...

     introduced September 1986
    ProDos16 uses MB in a binary sense.
    Similar usage in "ProDOS Technical Reference Manual" (c) 1985, p. 5 & p. 163
    Digital Large System Mass Storage Handbook (c) dated Sep 1986
    "GByte: An abbreviation for one billion (one thousand million) bytes." p. 442
    "M: An abbreviation for one million. Typically combined with a unit of measure, such as bytes (MBytes), or Hertz (MHz)." p444


    1987
    • Seagate
      Seagate Technology
      Seagate Technology is one of the world's largest manufacturers of hard disk drives. Incorporated in 1978 as Shugart Technology, Seagate is currently incorporated in Dublin, Ireland and has its principal executive offices in Scotts Valley, California, United States.-1970s:On November 1, 1979...

       Universal Installation Handbook
      • ST125 listed as 21 "Megabytes" formatted capacity, later document seems to confirm that this is decimal
    • Disk/Trend Report - Rigid Disk Drives, October 1987
      • First use of GB in a decimal sense in this HDD marketing survey; Figure 1 states "FIXED DISK DRIVES more than 1 GB" market size as $10,786.6 million.
    • Webster's Ninth New Collegiate Dictionary (1987) has binary definitions for kilobyte and megabyte.
      • kilobyte n [from the fact that 1024 (210) is the power of 2 closest to 1000] (1970): 1024 bytes
      • megabyte n (1970): 1,048,576 bytes


    1988
    • Imprimis
      Control Data Corporation
      Control Data Corporation was a supercomputer firm. For most of the 1960s, it built the fastest computers in the world by far, only losing that crown in the 1970s after Seymour Cray left the company to found Cray Research, Inc....

       Wren VII 5¼ Inch Rigid Disk Drive Data Sheet, printed 11/88
      • "Capacity of 1.2 gigabyte (GB)"


    1989
    • IBM
      IBM
      International Business Machines Corporation or IBM is an American multinational technology and consulting corporation headquartered in Armonk, New York, United States. IBM manufactures and sells computer hardware and software, and it offers infrastructure, hosting and consulting services in areas...

       Enterprise Systems Architecture/370, Reference Summary (GX20-0406-0), p50 (the last page), has a two table, one to recap the decimal value of power of 2 and 16 to 260, and one that read:
    {| class="wikitable"

    |-
    ! Symbol
    ! Value
    |-
    | K(kilo)
    | 1,024 = 210
    |-
    | M(mega)
    | 1,048,576 = 220
    |-
    | G(giga)
    | 1,073,741,824 = 230
    |}
    • Electronic News, Sep 25, "Market 1.5GB Drives"
      • "Imprimis and Maxtor
        Maxtor
        Maxtor Corporation, founded in 1982 and acquired by Seagate Technology in 2006, was an American manufacturer of computer hard disk drives, the third largest in the world immediately prior to acquisition...

         are the only two drive makers to offer the new generation of drives in the 1.5GB capacity range…"
      • "IBM, Hewlett-Packard, Fujitsu, Toshiba, Hitachi and Micropolis are expected to enter the market for 1.5GB capacity…"

    1990s
    1990s
    File:1990s decade montage.png|From left, clockwise: The Hubble Space Telescope floats in space after it was taken up in 1990; American F-16s and F-15s fly over burning oil fields and the USA Lexie in Operation Desert Storm, also known as the 1991 Gulf War; The signing of the Oslo Accords on...

    1990
    • GEOS
      GEOS (8-bit operating system)
      GEOS is an operating system from Berkeley Softworks . Originally designed for the Commodore 64 and released in 1986, it provided a graphical user interface for this popular 8-bit computer.GEOS closely resembled early versions of Mac OS and included a graphical word processor and paint program...

       ad
      • "512K of memory"
    June
    • DEC
      Digital Equipment Corporation
      Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...

       RA90/RA92 Disk Drive Service Manual
      • "Storage capacity, formatted" "1.216 gigabytes"


    1991
    • May 13: Apple releases Macintosh System 7 containing Finder 7.0 which uses M in a binary sense to describe HDD capacity.
      This is the first known instance of an operating system or utility using M in a binary sense.

    • Micropolis
      Micropolis (company)
      Micropolis Corporation was a disk drive company located in Chatsworth, California. The company was founded in 1976. Micropolis initially manufactured high capacity hard sectored 5.25 inch floppy drives and controllers...

       1528 Rigid Disk Drive Product Description
      • "1.53 GBytes" ... "Up to 1.53 gigabytes (unformatted) per drive" "MBytes/Unit: 1531.1" (2100×48,608×15 = 1,531,152,000)


    1994
    • Feb: Microsoft
      Microsoft
      Microsoft Corporation is an American public multinational corporation headquartered in Redmond, Washington, USA that develops, manufactures, licenses, and supports a wide range of products and services predominantly related to computing through its various product divisions...

       Windows for Workgroup 3.11
      Windows 3.1x
      Windows 3.1x is a series of 16-bit operating systems produced by Microsoft for use on personal computers. The series began with Windows 3.1, which was first sold during March 1992 as a successor to Windows 3.0...

       File Manager uses MB in a binary sense to describe HDD capacity.. Prior versions of Windows only used K in a binary sense to describe HDD capacity.

    • Micropolis 4410 Disk Drive Information
      • "1,052 MB Formatted Capacity"
      • "Unformatted Per Drive 1,205 MB" (133.85 MB per surface, 9 read-write heads)


    1996
    August
    • FOLDOC defines the exabyte
      Exabyte
      The exabyte is a unit of information or computer storage equal to one quintillion bytes . The unit symbol for the exabyte is EB...

       (1 EB) as 1024 petabyte
      Petabyte
      A petabyte is a unit of information equal to one quadrillion bytes, or 1000 terabytes. The unit symbol for the petabyte is PB...

      s (1024 PB), with petabyte used in the binary sense of 10245 B.
    December
    • Markus Kuhn
      Markus Kuhn
      Markus G. Kuhn is a German computer scientist, currently teaching and researching at the University of Cambridge Computer Laboratory. A graduate of the University of Erlangen , he received his MSc at Purdue University and PhD at the University of Cambridge...

       proposes a system with di prefixes, like the "dikilobyte" (K₂B) and "digigabyte" (G₂B). Did not see significant adoption.

    1997
    May
    • FOLDOC defines the zettabyte
      Zettabyte
      A zettabyte is a unit of information or computer storage equal to one sextillion bytes....

       (1 ZB) as 1024 exabytes (1024 EB) and the yottabyte
      Yottabyte
      The yottabyte is a unit of information or computer storage equal to one septillion bytes .The unit symbol for the yottabyte is YB....

       (1 YB) as 1024 zettabytes (1024 ZB).

    1998
    • IEC
      International Electrotechnical Commission
      The International Electrotechnical Commission is a non-profit, non-governmental international standards organization that prepares and publishes International Standards for all electrical, electronic and related technologies – collectively known as "electrotechnology"...

       introduces unambiguous prefixes for binary multiples (KiB
      Kibibyte
      The kibibyte is a multiple of the unit byte for quantities of digital information. The binary prefix kibi means 1024; therefore, 1 kibibyte is . The unit symbol for the kibibyte is KiB. The unit was established by the International Electrotechnical Commission in 1999 and has been accepted for use...

      , MiB
      Mebibyte
      The mebibyte is a multiple of the unit byte for digital information. The binary prefix mebi means 220, therefore 1 mebibyte is . The unit symbol for the mebibyte is MiB. The unit was established by the International Electrotechnical Commission in 2000 and has been accepted for use by all major...

      , GiB
      Gibibyte
      The gibibyte is a standards-based binary multiple of the byte, a unit of digital information storage. The gibibyte unit symbol is GiB....

       etc.), reserving kB, MB, GB and so on for their decimal sense.

    1999
    • Donald Knuth
      Donald Knuth
      Donald Ervin Knuth is a computer scientist and Professor Emeritus at Stanford University.He is the author of the seminal multi-volume work The Art of Computer Programming. Knuth has been called the "father" of the analysis of algorithms...

      , who uses decimal notation like 1 MB = 1000 kB, expresses "astonishment" that the IEC proposal was adopted, calling them "funny-sounding", and proposes that the powers of 1024 be designated as "large kilobytes" and "large megabytes" (abbreviated KKB and MMB, as "doubling the letter connotes both binary-ness and large-ness"). Double prefixes were formerly used with SI, however, with a multiplicative meaning ("MMB" would be equivalent to "TB"), and this proposed usage never gained any traction.

    2000s

    2001
    • IBM, z/Architecture
      Z/Architecture
      z/Architecture, initially and briefly called ESA Modal Extensions , refers to IBM's 64-bit computing architecture for IBM mainframe computers. IBM introduced its first z/Architecture-based system, the zSeries Model 900, in late 2000. Later z/Architecture systems include the IBM z800, z990, z890,...

      , Reference Summary
      • Page 59, list the power of 2 and 16, and their decimal value. There is a column name 'Symbol', which list K(kilo), M(mega), G(giga), T(tera), P(peta) and E(exa) for the power of 2 of, respectively, 10, 20, 30, 40, 50, 60

    • Peuhkuri adopts IEC prefixes in his paper at the 2001 Internet Measurement Conference: "... allows maximum size of 224 that requires 1 GiB of RAM ... or acknowledgement numer [sic] is within 32 KiB range. ... on a PC with Celeron processor with 512 MiB of memory ... "

    • The Linux kernel
      Linux kernel
      The Linux kernel is an operating system kernel used by the Linux family of Unix-like operating systems. It is one of the most prominent examples of free and open source software....

       uses IEC prefixes.

    2004
    • 2004 revision of IEEE Standard Letter Symbols for Units of Measurement (SI Units, Customary Inch-Pound Units, and Certain Other Units), IEEE Std 260.1, incorporates IEC definitions for KiB, MiB etc, reserving the symbols kB, MB etc for their decimal counterparts.


    2005
    March
    • IEC prefixes are adopted by the IEEE after a two-year trial period.
      • On March 19, 2005 the IEEE standard IEEE 1541
        IEEE 1541
        IEEE 1541-2002 is a standard issued by the Institute of Electrical and Electronics Engineers concerning the use of prefixes for binary multiples of units of measurement related to digital electronics and computing....

        -2002 (Prefixes for Binary Multiples) was elevated to a full-use standard by the IEEE Standards Association after a two-year trial period.


    2007
    • Windows Vista
      Windows Vista
      Windows Vista is an operating system released in several variations developed by Microsoft for use on personal computers, including home and business desktops, laptops, tablet PCs, and media center PCs...

       uses the binary conventions (e.g., 1 KB = 1024 bytes, 1 MB = 1048576 bytes) for file and drive sizes, and for data rates
    • GParted
      GParted
      GParted is a GTK+ front-end to GNU Parted and the official GNOME Partition Editor application.It is used for creating, deleting, resizing, moving, checking and copying partitions, and the file systems on them...

       uses IEC prefixes for partition sizes
    • Advanced Packaging Tool
      Advanced Packaging Tool
      The Advanced Packaging Tool, or APT, is a free user interface that works with core libraries to handle the installation and removal of software on the Debian GNU/Linux distribution and its variants...

       and Synaptic Package Manager
      Synaptic Package Manager
      Synaptic is a computer program which is a GTK+ graphical user interface front-end to the Advanced Packaging Tool for the Debian package management system. Synaptic is usually used on systems based on deb packages but can also be used on systems based on RPM packages...

       use standard SI prefixes for file sizes
    • BitTornado
      BitTornado
      BitTornado is a free BitTorrent client for transfer of computer files over networks, including the Internet. It is developed by John Hoffman, who also created its predecessor, Shad0w's Experimental Client...

       uses IEC prefixes for file sizes and standard SI prefixes for data rates
    • IBM uses "exabyte" to mean 10246 bytes. "Each address space, called a 64-bit address space, is 16 exabytes (EB) in size; an exabyte is slightly more than one billion gigabytes. The new address space has logically 264 addresses. It is 8 billion times the size of the former 2-gigabyte address space, or 18,446,744,073,709,600,000 bytes."


    2008
    • The US National Institute of Standards and Technology guidelines require use of IEC prefixes KiB, MiB ... (and not kB, MB) for binary byte multiples
      • p29, “The names and symbols for the prefixes corresponding to 2 10 , 2 20 , 2 30 , 2 40 , 2 50 , and 2 60 are, respectively: kibi, Ki; mebi, Mi; gibi, Gi; tebi, Ti; pebi, Pi; and exbi, Ei. Thus, for example, one kibibyte is also written as 1 KiB = 2 10 B = 1024 B, where B denotes the unit byte. Although these prefixes are not part of the SI, they should be used in the field of information technology to avoid the non-standard usage of the SI prefixes.”


    2009
    • Apple Inc. uses the SI decimal definitions for capacity (e.g., 1 kilobyte = 1000 bytes) in the Mac OS X v10.6
      Mac OS X v10.6
      Mac OS X Snow Leopard is the seventh major release of Mac OS X, Apple's desktop and server operating system for Macintosh computers.Snow Leopard was publicly unveiled on June 8, 2009 at the Apple Worldwide Developers Conference...

       operating system to conform with standards body recommendations and avoid conflict with hard drive manufacturers' specifications.

    2010s

    2010
    • The ubuntu operating system uses the SI prefixes for base-10 numbers and IEC prefixes for base-2 numbers as of the 10.10 release.
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