Talk:Timeline of binary prefixes

Graphical timeline
Earliest and latest instances of each notation that appear in the above list. This is not for the article, but just for our own internal use here. It's not actually accurate, since we haven't found everything yet, and is too close to original research to put in the article. (I guess it would make more sense to track each thing, like hard drives/memory/data rates, separately):

Ludwig
I removed the statement "The computer has two blocks of 4K, 18-bit words of memory, (1K=1024 words), attached to its central processor" as it was incorrectly attributed to Ludwig 1963. Does anyone know where it is from? Thunderbird2 (talk) 16:13, 20 June 2008 (UTC)
 * It's from Gordon Bell. Ghettoblaster (talk) 22:21, 23 June 2008 (UTC)

Deleted everything before 1998
Binary prefixes didn't exist before 1998. This entire timeline seems like more of a history of electronic storage than of binary prefixes. We already have other articles for that. I am going to delete everything before 1998 and replace it with a short paragraph saying that the KB, MB and GB were ambiguously defined in different contexts. Since no one is actually reading this, I'm going to go ahead and do it. However if you disagree, then revert and explain why here.--RaptorHunter (talk) 06:17, 12 April 2011 (UTC)
 * seems to me that it was either explicitly about binary prefixes; or at least about binary use of prefixes. Perhaps the title should be changed to better reflect the scope. Dondervogel 2 (talk) 18:10, 12 April 2011 (UTC)
 * Customary binary prefixes began as early as 1964. I see no need to change anything other than perhaps add a clarification to the lead that the timeline starts with the use of the words bit and byte. Tom94022 (talk) 18:51, 12 April 2011 (UTC)

Binary vs decimal addressing
This article ignores an important distinction in early computer history: many early machines used decimal addressing (ENIAC, UNIVAC 1, IBM 702, 705, 650, 1400s, 1620, etc.) while others used binary addressing (Colossus, Whirlwind, FSQ-7, IBM 701, 704, 709, 7090, etc). Of course decimal machines reported memory in decimal multiples and K, if it was used, meant 1000. It was only in binary machines that memory came in powers of two or multiples of 1024 units. It was just with binary addressed machines that K took on its second meaning as an informal shortcut for 1024. Only in the mid 60s with the introduction of the IBM System/360 did binary addressing became universal in the computer industry. By not making this distinction clearly, the article muddles what was really going on.--agr (talk) 23:53, 28 April 2011 (UTC)


 * Actually most are listed in the preamble to this article and some are listed in the body (notably absent Eniac and Univac 1). The issue is not so much whether computers used decimal or binary addressing but whether in describing the memory space they used prefixes or not and, when used were the prefixes in a decimal, binary or vague state.  For example, absent other information 16K is ambiguous and it is not until we see 64K versus 65K can we reach any conclusion as to the author's intent.  I agree with your view of history but suggest that the place to make the distinction is not in this timeline but in the related main memory section of the Binary_prefix article where the history is beyond muddled to the point of misrepresenting the co-evolution of binary and decimal prefixes in main memory.  Tom94022 (talk) 17:48, 3 May 2011 (UTC)


 * I took a quick walk thru Univac 1 material including a full text search of its Manual Of Operation and concluded that Remington Rand then made little use of any prefixes in describing the product. I could find no instances of use of any prefix in describing memory or tape capacity.  I did find several instances of million and mega in a decimal sense as in, "the "rep rate" is assumed to be 1,000,000 pulses per second or a frequency of 1 megacycle, (1,000,000 cycles per second)." (emphasis added, from p.21 of linked doc above).  I'm not sure a negative report is worth adding to this timeline and it might be OR.  Tom94022 (talk) 18:29, 4 May 2011 (UTC)

Thanks, I made some edits at Binary_prefix. Also see my comments at Talk:Hard disk drive. The problem is that this all started as informal usage, so it's hard to document original intent. K=1024 only becomes important once memory gets much bigger than 32K and that came with the third generation of computers, mid 60s. Before then everyone was comfortable saying 32K for 32768, but if you had asked them they would have said K means 1000. Even the distinction between 64K and 65K usage didn't matter. Everyone knew what was meant. I remember being told K means 1024 in memory size and finding the idea sort of weird until I got used to it. --agr (talk) 20:51, 4 May 2011 (UTC)

When did Exabyte appear?
The article claims "exabyte" was defined in 1996. It was in use years before that.

According to http://en.wikipedia.org/wiki/Exabyte_(company) the company called "Exabyte" was started in 1985. They picked the name because Exabyte not in some small way to be comical: exabytes were so huge nobody would ever have a storage system that large. Therefore, we know the term existed that early.

I haven't been able to find a reference that gives the exact year.

TomLimoncelli (talk) 20:34, 12 July 2012 (UTC) TomLimoncelli


 * I added the founding of Exabyte to the timeline, along with the years that the various SI prefixes giga, tera, exa, peta, zetta and yotta were introduced. Kilo and mega are from before the 1940s.  Once the prefixes are introduced, all combinations are understandable. For what it's worth, I remember megabyte being used in meeting 1970 and the term was familiar then. I also remember when I first heard the term gigabyte, in the early 70s, and that was quite startling. (I visited an apparel manufacturer that had one of the first IBM commercial installations with no magnetic tape drives. The system had racks of disk pack drives that totaled 3 gigabytes. It ran their entire business.) --agr (talk) 21:37, 12 July 2012 (UTC)

IBM WebSphere
According to this page, the text making use of the binary prefixes KiB, MiB, etc, is dated 5 December 2008. Dondervogel 2 (talk) 23:20, 10 March 2014 (UTC)

See also 'Smart SOA Connectivity Patterns: Unleash the Power of IBM WebSphere Connectivity Portfolio', Virendar Solanki et al (IBM Redbooks, September 2011). Dondervogel 2 (talk) 23:37, 10 March 2014 (UTC)

Decimal vs binary meanings of 'terabyte'
There is a discussion of the decimal and binary meanings of 'terabyte' at Talk:Terabyte. The discussion has possible implications for this page. If you wish to comment, please do so on the terabyte talk page. Dondervogel 2 (talk) 10:54, 29 July 2015 (UTC)

External links modified
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Table removed from article on OR grounds - place here because analysis seems relevant for discussion on Talk page

 * The following statistics were taken from the December 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 -- (unsigned) 2016-09-11T11:13:28 Dondervogel 2
 * 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
 * }
 * Mb             || 2 / 2   || 1 / 3
 * M              || 1 / 1   ||
 * Total          || 20 / 43 || 2 / 4
 * }
 * Total          || 20 / 43 || 2 / 4
 * }
 * }

The article title is narrower than the topic of the article
The article is more like "timeline of measurement prefixes", as it discusses the use of both K/M/G/T/... and Ki/Mi/Gi/Ti prefixes, as well as the use of no prefixes, just giving counts of individual bytes or words.

And it starts out discussing the origins of both decimal and binary prefixes. Guy Harris (talk) 03:05, 22 March 2020 (UTC)


 * I don't see the problem. The article starts by introducing the origin of binary prefixes in the 1790s. There was a btw statement about the decimal prefixes d, c and m that I have just removed. All other metric prefixes (as well as the "no prefix" examples) are there to give context to the binary ones.
 * Can you be more specific? Perhaps suggest an improvement? Dondervogel 2 (talk) 22:43, 22 March 2020 (UTC)


 * Re-opening this. I note that in the thread below I independently commented: "The title is does not perfectly reflect the scope of the article, which misled me. With the broader scope as described in the lead, contributing events are listed in the article."  It would be helpful to align the article title more closely with the description in the first paragraph of the lead.  How about this as a starting suggestion to work from?
 * Timeline of events related to the evolution of binary prefixes
 * List of events related to the evolution of binary prefixes
 * —Quondum 15:05, 31 May 2024 (UTC)
 * I'm struggling to understand the benefit of a longer title. To me the evolution part is implied by "timeline", which suggests your first option could be shortened to "Timeline of events related to binary prefixes", which could then be shortened further to "Timeline of binary prefixes" without changing the meaning. What am I missing? Dondervogel 2 (talk) 20:27, 31 May 2024 (UTC)
 * "without changing the meaning" – I disagree here. There is an additional degree of context included by "related to".  It is clear that it is not only I who does not read these as synonymous.  One could shorten it to Timeline related to binary prefixes (though this seems a little unnatural to me).  My original objections resulted on this difference.  Then I saw the inclusion of metric prefixes, and thought those (and many other snippets) really do not fit as part of the binary prefixes, but they kinda make sense if you want to give enough context for a fuller understanding.  Then I read the first sentence of the lead, and I thought, yes, stated that way, they fit, because that is a much broader description than the meaning of the title.  I want to avoid that reaction in others who come to this article.  Its existence is to give the broader context, not just to recount the timeline of the evolution of binary prefixes, which would start with the first use of a binary prefix (which, I imagine, in unambiguous form, was in 1964).  —Quondum 16:26, 1 June 2024 (UTC)
 * It seems clear to me that the first unambiguous use of a binary prefix was in 1793.
 * I don't feel strongly about the title. I don't see a need to change but would not oppose one either.
 * Dondervogel 2 (talk) 17:43, 1 June 2024 (UTC)
 * 1793: conceded. Let's qualify my statement to binary prefixes in the 1024$n$ sequence.
 * I would like to see comment from others on the topic of title choice. —Quondum 18:45, 1 June 2024 (UTC)
 * Pinging and, in case you have any feelings/suggestions on a title that properly reflects the article topic (its first sentence possibly being a good encapsulation).  —Quondum 11:29, 3 June 2024 (UTC)
 * , thx for the heads up. I'm quite OK with the title as it is and it shouldn't be any longer (becoming unwieldy), even though there are several entries not really about prefixes and only making sense in the larger, general context. --Zac67 (talk) 13:27, 3 June 2024 (UTC)

How is IEEE 802.11 relevant to a timeline of binary prefixes?
I didn't understand this edit Dondervogel 2 (talk) 15:56, 29 May 2024 (UTC)


 * The text said
 * The IEEE 802.11-1999 standard introduces the binary time unit TU defined as 1024 μs (10−6 Kis).
 * The parenthesis and the inclusion in the article suggest that it is relevant to the prefix 'Ki'. It seems unlikely that the IEEE standard used that prefix in that context.  The source uses "kilo-microseconds"/"1 kμs", evidently with "kilo"/"k" in the binary sense and "micro"/"μ" in the decimal sense, without mentioning "kibi"/"Ki".  The origin of 1024 μs is presumably the binary divider ratio from 1 MHz in hardware as an approximation of 1 ms, but that has no reason to be associated with a prefix in that context.  Unless we are trying to claim that the source used "k" in the binary sense here (in which case the mention of an IEEE standard is misleading), what is the point of the statement in the article?
 * If I am wrong, and the IEEE standard does use the prefix "kilo"/"kibi"/"k"/"Ki" in the binary sense here, we should cite the standard, not the source used. But I would be rather surprised if this were the case.  —Quondum 16:55, 29 May 2024 (UTC)
 * From your reply, I conclude that the standard is indeed using the prefix "k" in the binary sense. Isn't that reason enough to keep the example, albeit with better wording? I see that in the meantime your edit was reverted by another editor. Dondervogel 2 (talk) 17:33, 29 May 2024 (UTC)
 * The article IEEE 802.11 (legacy mode) says "IEEE 802.11-1999 also introduced the binary time unit TU defined as 1024 μs." This makes sense aside from the use of the word "binary", which does not occur in the source.  I have serious doubts that IEEE used any form of binary prefix in its definition of the TU, however.  The source uses its prefixes in an unforgivingly mangled and confusing way that IMO never would have been included in a standard.  So unless someone has access to the text of the standard, I do not think that the source's manner of expression should be attributed to the standard.  The parenthesis was added here, presumably intended as clarification, but introducing the presumably unwarranted implication that "Kis" was similarly in the IEEE definition of the TU, but without citing the IEEE standard.  Without the parenthesis and this implication, the statement "The IEEE 802.11-1999 standard introduces the [binary] time unit TU defined as 1024 μs", seems to be devoid of relevance to the article Timeline of binary prefixes.  What am I missing?  —Quondum 18:26, 29 May 2024 (UTC)
 * I think the relevance arises from statements like "One Kµsec equals 1,024 microseconds" Dondervogel 2 (talk) 19:04, 29 May 2024 (UTC)
 * That is an example of 'K' being used to mean kilobinary (in compound with SI prefixes – ugh). If you wish, this could be listed as an example of the use of the binary 'K' in 2009.  I don't see it as a case for listing it in 1999.  —Quondum 19:31, 29 May 2024 (UTC)
 * I'm going to modify my position slightly. The title is does not perfectly reflect the scope of the article, which misled me.  With the broader scope as described in the lead, contributing events are listed in the article.  As such the IEEE standard provides an event that is related to a few later uses of binary prefixes (albeit only 'k' and 'K' in a binary sense that I have seen).  I still think the parenthesis "(10−6 Kis)" leads the reader down the wrong path, and should be deleted.  A few of those later uses in relation to the TU have been identified (the use in the source itself, and in another case that is linked above).  The relevance of the IEEE definition would be clearer if those, or similar, were listed under later dates mentioning these actual uses of prefix with a binary sense.  —Quondum 21:29, 29 May 2024 (UTC)


 * IEEE 802.11 don't use any prefix with 1 TU = 1024 μs – so where exactly is the relevance for this article? --Zac67 (talk) 06:18, 30 May 2024 (UTC)
 * The relevance becomes apparent when a time unit (1024 us) is referred to as a "kilomicrosecond". A "microkibisecond" seems less inappropriate, albeit only slightly. Dondervogel 2 (talk) 11:02, 30 May 2024 (UTC)
 * See also Jackman, S. M., Swartz, M., Burton, M., & Head, T. W. (2011). CWDP Certified Wireless Design Professional Official Study Guide: Exam PW0-250. John Wiley & Sons Dondervogel 2 (talk) 11:05, 30 May 2024 (UTC)
 * Then it's not about IEEE 802.11 but depends on another site/organization. https://www.jstage.jst.go.jp/article/ieejeiss/134/4/134_543/_pdf talks about "kilomicrosecond" (decimal or binary isn't stated) but doesn't use 802.11's "TU", so it's not relevant here. I can't verify Certified Wireless Design Professional Official Study Guide: Exam PW0-250 but suspect the same. A source for prefix usage would need to refer to 1024 as "K" or "Ki" in the required context to qualify. As it stands, "(10−6 Kis)" is original (yet trivial) research. Instead, the passage would need to refer to the book it currently uses as source. The implied use by 802.11 is non-existent, and usage elsewhere needs to be relevant to be mentioned. --Zac67 (talk) 12:56, 30 May 2024 (UTC)
 * Use of Kis is a trivial unit conversion (i.e., not OR). One Kµsec equals 1,024 microseconds is an example of a binary prefix. Another is A Time Unit (TU) is 1024 microseconds (a ``kilo-microsecond or ``kus). I imagine there are plenty of others. And you still need 802.11 in the timeline to give the reader a chance to comprehend the other nonsense. Dondervogel 2 (talk) 18:54, 30 May 2024 (UTC)
 * Hoo-boy. "The result is that bit 31 rolls over at something close to but not exactly one second. Apparently believing in time dilation, IBM calls this a megamicrosecond."  Indeed, here it is: "mega-microsecond (p. 290)  —Quondum 19:42, 30 May 2024 (UTC)
 * Great find. Here's a couple more - Lol
 * A mega-microsecond (MUS) is 2**20 microseconds
 * This interval is sometimes called a "mega-microsecond" (Mfis).
 * It occurs every megamicrosecond – Mus (1.048576 seconds)
 * I suspect "Mfis" is "Mus" (or "Mμs") in the original
 * Now we are talking "mebimicroseconds" (1e-6 Mis). Dondervogel 2 (talk) 22:54, 30 May 2024 (UTC)
 * All true, but the entry at hand is (currently, thx for the update): "The IEEE 802.11-1999 standard introduces the binary time unit TU defined as 1024 μs." - where is there a binary prefix? The other sources seem to be valid, but not directly related to 802.11's TU. --Zac67 (talk) 04:54, 31 May 2024 (UTC)
 * The relevance is in the accompanying quote: "The units for the Beacon Interval field are kilo-microseconds (1,024 μs). In the IEEE 802.11-1999 specification, the term 'Time Unit' is introduced, and defined such that one Time Unit is equal to 1 kμs (i.e., one Time Unit is equal to 1.024 ms)." The statement was made in 2004, so perhaps belongs further down the article. The first mention of "megamicrosecond" was Smith et al (1991), so that one belongs further up. Dondervogel 2 (talk) 06:26, 31 May 2024 (UTC)
 * Once the uses that you mention (and perhaps others not yet included) are given their own entries, the IEEE definition of the TU will be incorporated by reference where the quotes refer to it. The question will then become: is the IEEE definition of the TU in itself an event that is germane to the development and use of binary prefixes?  I don't have a clear answer to this in my mind.  The argument might run that the definition of the TU served to catalyze the coining of "k&mu;s" and similar, but it could equally well be that it had no impact, and was just mentioned for its applicability/interchangeability in the same contexts.  It seems likely that the coining of these binary–decimal composites preceded the definition of the TU.  —Quondum 11:55, 31 May 2024 (UTC)
 * Apparently, the use of "kilo-microsecond" or similar predates the 802.11 definition, so it's debatable whether IEEE is relevant here at all. For now, I have rephrased so that it's clearer only further reference makes that use. --Zac67 (talk) 13:40, 31 May 2024 (UTC)
 * I suggest that the actual uses be given entries at the appropriate dates (if deemed sufficiently notable, but the bar is not high here). Then it might make sense to revisit inclusion of this entry.  —Quondum 14:27, 31 May 2024 (UTC)
 * makes sense Dondervogel 2 (talk) 14:40, 31 May 2024 (UTC)
 * I added the earliest mention I could find of "kilomicrosecond" (2004) and "megamicrosecond" (1991), so now could be the time to revisit the relevance of IEEE 802.11. My preference is to keep it, as it seems relevant to (later) use of kilomicrosecond to mean 1024 μs. Dondervogel 2 (talk) 09:00, 1 June 2024 (UTC)
 * Interesting. I thought that the TU might seem relevant enough (in the sense that it might be a formal replacement of what was called a kilomicrosecond) to keep a reference to it under a kilomicrosecond or similar entry.  Now it seems to me that it may be entirely incidental, in the sense that it was a useful enough interval of time to define a unit for, but we have nothing to indicate what its relationship might be, aside from the later indications that they are equal as quantities.  —Quondum 18:58, 1 June 2024 (UTC)

Pre-1975 "Byte magazine" references?
back in 2011 you added some items that cited pre-1975 issues of "Byte Magazine", but Byte (magazine) says that magazine's first issue was in September 1975. Is this some earlier magazine, also named "Byte"? Guy Harris (talk) 20:52, 7 July 2024 (UTC)
 * My bad, it was Datamation; corrected. Tom94022 (talk) 05:39, 8 July 2024 (UTC)
 * I figured it was one of those DP magazines (Datamation, Computerworld, etc.). Thanks. Guy Harris (talk) 06:06, 8 July 2024 (UTC)