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.infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox hproduct vevent"><caption class="infobox-title fn summary">English Electric KDF9</caption><tbody><tr><th scope="row" class="infobox-label">Developer</th><td class="infobox-data"><a href="/wiki/English_Electric" title="English Electric">English Electric</a></td></tr><tr><th scope="row" class="infobox-label">Manufacturer</th><td class="infobox-data"><a href="/wiki/English_Electric" title="English Electric">English Electric</a></td></tr><tr><th scope="row" class="infobox-label">Generation</th><td class="infobox-data">2</td></tr><tr><th scope="row" class="infobox-label">Release date</th><td class="infobox-data">1964<span class="noprint">; 61 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">1964</span>)</span></td></tr><tr><th scope="row" class="infobox-label">Units shipped</th><td class="infobox-data">29</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Operating_system" title="Operating system">Operating system</a></th><td class="infobox-data">Timesharing Director, Eldon 2, EGDON, COTAN</td></tr><tr><th scope="row" class="infobox-label"><a href="/wiki/Central_processing_unit" title="Central processing unit">CPU</a></th><td class="infobox-data">Transformer-coupled <a href="/wiki/Diode%E2%80%93transistor_logic" title="Diode–transistor logic">diode–transistor logic</a>, built from germanium diodes, about 20,000 transistors, and about 2,000 toroid pulse transformers) @ 1 MHz</td></tr><tr><th scope="row" class="infobox-label">Memory</th><td class="infobox-data">32K words of 48-bit core storage (192K bytes)</td></tr><tr><th scope="row" class="infobox-label">Weight</th><td class="infobox-data">5.2 short tons (4.7 t)</td></tr></tbody></table> <p><b>KDF9</b> was an early British <a href="/wiki/48-bit_computing" title="48-bit computing">48-bit</a> computer designed and built by <a href="/wiki/English_Electric" title="English Electric">English Electric</a> (which in 1968 was merged into <a href="/wiki/International_Computers_Limited" title="International Computers Limited">International Computers Limited</a> (ICL)). The first machine came into service in 1964 and the last of 29 machines was decommissioned in 1980 at the <a href="/wiki/National_Physical_Laboratory_(United_Kingdom)" title="National Physical Laboratory (United Kingdom)">National Physical Laboratory</a>. The KDF9 was designed for, and used almost entirely in, the mathematical and scientific processing fields –  in 1967, nine were in use in UK universities and technical colleges.<sup id="cite_ref-hansard-19670306_1-0" class="reference"><a href="#cite_note-hansard-19670306-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> The <a href="/wiki/KDF8" class="mw-redirect" title="KDF8">KDF8</a>, developed in parallel, was aimed at commercial processing workloads. </p><p>The KDF9 was an early example of a machine that directly supported <a href="/wiki/Multiprogramming" class="mw-redirect" title="Multiprogramming">multiprogramming</a>, using offsets into its <a href="/wiki/Core_memory" class="mw-redirect" title="Core memory">core memory</a> to separate the programs into distinct virtual address spaces. Several <a href="/wiki/Operating_system" title="Operating system">operating systems</a> were developed for the platform, including some that provided fully interactive use through <a href="/wiki/PDP-8" title="PDP-8">PDP-8</a> machines acting as smart <a href="/wiki/Terminal_server" title="Terminal server">terminal servers</a>. A number of <a href="/wiki/Compiler" title="Compiler">compilers</a> were available, notably both checkout and globally optimizing compilers for <a href="/wiki/Algol_60" class="mw-redirect" title="Algol 60">Algol 60</a>. </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Architecture">Architecture</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=1" title="Edit section: Architecture"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The logic circuits of the KDF9 were entirely <a href="/wiki/Solid-state_electronics" title="Solid-state electronics">solid-state</a>. The KDF9 used transformer-coupled <a href="/wiki/Diode%E2%80%93transistor_logic" title="Diode–transistor logic">diode–transistor logic</a>, built from germanium diodes, about 20,000 transistors, and about 2,000 toroid <a href="/wiki/Pulse_transformer" class="mw-redirect" title="Pulse transformer">pulse transformers</a>.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> They ran on a 1 MHz clock that delivered two pulses of 250 ns separated by 500 ns, in each clock cycle. The maximum configuration incorporated 32K words of 48-bit core storage (192K bytes) with a cycle time of 6 microseconds. Each word could hold a single 48-bit integer or <a href="/wiki/Floating-point" class="mw-redirect" title="Floating-point">floating-point</a> number, two 24-bit integer or floating-point numbers, six 8-bit instruction <a href="/wiki/8-bit_syllable" class="mw-redirect" title="8-bit syllable">syllables</a>, or eight 6-bit characters.<sup id="cite_ref-EE_1961_3-0" class="reference"><a href="#cite_note-EE_1961-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> There was also provision for efficient handling of double-word (96-bit) numbers in both integer and floating-point formats. However, there was no facility for byte or character addressing, so that non-numerical work suffered by comparison. Its standard character set was a version of the <a href="/wiki/Friden_Flexowriter" title="Friden Flexowriter">Friden Flexowriter</a> paper tape code that was oriented to Algol 60, and included unusual characters such as the Algol subscript 10. However, each other I/O device type implemented its own subset of that. Not every character that could be read from paper tape could be successfully printed, for example. </p> <div class="mw-heading mw-heading3"><h3 id="Registers">Registers</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=2" title="Edit section: Registers"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The CPU architecture featured three register sets. The <i>Nest</i> was a 16-deep pushdown stack of arithmetic registers, The <i>SJNS</i> (Subroutine Jump Nesting Store) was a similar stack of return addresses. The <i>Q Store</i> was a set of 16 index registers, each of 48 bits divided into <i>Counter</i> (C), <i>Increment</i> (I) and <i>Modifier</i> (M) parts of 16 bits each. Flags on a memory-reference instruction specified whether the address should be modified by the M part of a Q Store, and, if so, whether the C part should be decremented by 1 and the M part incremented by the contents of the I part. This made the coding of counting loops very efficient. Three additional Nest levels and one additional SJNS level were reserved to Director, the Operating System, allowing short-path interrupts to be handled without explicit register saving and restoring. As a result, the interrupt overhead was only three clock cycles. </p> <div class="mw-heading mw-heading3"><h3 id="Instruction_set">Instruction set</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=3" title="Edit section: Instruction set"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Instructions were of one, two, or three syllables. Although the word '<a href="/wiki/Byte" title="Byte">byte</a>' had been coined by the designers of the <a href="/wiki/IBM_7030_Stretch" title="IBM 7030 Stretch">IBM 7030 Stretch</a> for a group of eight <a href="/wiki/Bit" title="Bit">bits</a>, it was not yet well known, and English Electric used the word '<a href="/wiki/Syllable_(computing)" title="Syllable (computing)">syllable</a>' for what is now called a byte. Most arithmetic took place at the top of the Nest and used <i><a href="/wiki/Zero_address_arithmetic" class="mw-redirect" title="Zero address arithmetic">zero-address</a></i>, one-syllable instructions, although address arithmetic and index updating were handled separately in the Q store. Q Store handling, and some memory reference instructions used two syllables. Memory reference instructions with a 16-bit address offset, most jump instructions, and 16-bit literal load instructions, all used 3 syllables. </p><p><a href="/wiki/Code_density" class="mw-redirect" title="Code density">Dense instruction coding</a>, and intensive use of the register sets, meant that relatively few store accesses were needed for common scientific codes, such as <a href="/wiki/Scalar_product" class="mw-redirect" title="Scalar product">scalar product</a> and polynomial inner loops. This did much to offset the relatively slow core cycle time, giving the KDF9 about a third of the speed of its much more famous, but 8 times more expensive and much less commercially successful contemporary, the Manchester/<a href="/wiki/Ferranti" title="Ferranti">Ferranti</a> <a href="/wiki/Atlas_Computer" class="mw-redirect" title="Atlas Computer">Atlas Computer</a>. </p> <div class="mw-heading mw-heading3"><h3 id="Multiprogramming_(timesharing)"><span id="Multiprogramming_.28timesharing.29"></span>Multiprogramming (timesharing)</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=4" title="Edit section: Multiprogramming (timesharing)"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The KDF9 was one of the earliest fully hardware-secured multiprogramming systems. Up to four programs could be run at once under the control of its elegantly simple operating system, the <i>Timesharing Director</i>, each being confined to its own core area by BA (Base Address) and NOL (Number of Locations) registers. Each program had its own sets of stack and Q store registers, which were activated when that program was dispatched, so that context switching was very efficient. </p><p>Each program could drive hardware I/O devices directly, but was limited by hardware checks to those that the Director had allocated to it. Any attempt to use an unallocated device caused an error interrupt. A similar interrupt resulted from overfilling (or over-emptying) the Nest or SJNS, or attempting to access storage at an address above that given in the NOL register. Somewhat different was the Lock-Out interrupt, which resulted from trying to access an area of store that was currently being used by an I/O device, so that there was hardware mutual exclusion of access to DMA buffers. When a program blocked on a Lock-Out, or by voluntarily waiting for an I/O transfer to terminate, it was interrupted and Director switched to the program of highest priority that was not itself blocked. When a Lock-Out cleared, or an awaited transfer terminated, and the responsible program was of higher priority than the program currently running, the I/O Control (IOC) unit interrupted to allow an immediate context switch. IOC also made provision to avoid priority inversion, in which a program of high priority waits for a device made busy by a program of lower priority, requesting a distinct interrupt in that case. </p><p>Later operating systems, including Eldon 2<sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> at the University of Leeds, and COTAN, developed by UKAEA Culham Laboratories with the collaboration of Glasgow University, were fully interactive multi-access systems, with <a href="/wiki/PDP-8" title="PDP-8">PDP-8</a> front ends to handle the terminals. </p><p>The Kidsgrove and Whetstone Algol 60 compilers were among the first of their class. The Kidsgrove compiler stressed optimization; the Whetstone compiler produced an interpretive object code aimed at debugging. It was by instrumenting the latter that Brian Wichmann obtained the statistics on program behaviour that led to the <a href="/wiki/Whetstone_(benchmark)" title="Whetstone (benchmark)">Whetstone</a> benchmark for scientific computation,<sup id="cite_ref-5" class="reference"><a href="#cite_note-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> which inspired in turn the <a href="/wiki/Dhrystone" title="Dhrystone">Dhrystone</a> benchmark for non-numerical workloads.<sup id="cite_ref-crit1_6-0" class="reference"><a href="#cite_note-crit1-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Reminiscence">Reminiscence</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=5" title="Edit section: Reminiscence"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Machine code orders were written in a form of <a href="/wiki/Octal" title="Octal">octal</a> officially named <i><a href="/wiki/Syllabic_octal" class="mw-redirect" title="Syllabic octal">syllabic octal</a></i><sup id="cite_ref-EE_Director_7-0" class="reference"><a href="#cite_note-EE_Director-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> (also known as 'slob-octal' or 'slob' notation,<sup id="cite_ref-Beard_1997_8-0" class="reference"><a href="#cite_note-Beard_1997-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-CCS_2009_9-0" class="reference"><a href="#cite_note-CCS_2009-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup>). It represented 8 bits with three octal digits but the first digit represented only the two most-significant bits, whilst the others the remaining two groups of three bits each. </p><p>Within English Electric, its predecessor, <a href="/wiki/English_Electric_DEUCE" title="English Electric DEUCE">DEUCE</a>, had a well-used matrix scheme based on GIP (General Interpretive Programme). The unreliability of valve machines led to the inclusion of a <a href="/wiki/Summation_check" title="Summation check">sum-check</a> mechanism to detect errors in matrix operations.<sup id="cite_ref-NB_Sum_check_10-0" class="reference"><a href="#cite_note-NB_Sum_check-10"><span class="cite-bracket">[</span>nb 1<span class="cite-bracket">]</span></a></sup> The scheme used block floating-point using fixed-point arithmetic hardware, in which the sum-checks were precise. However, when the corresponding scheme was implemented on KDF9, it used floating point, a new concept that had only limited mathematical analysis. It quickly became clear that sum checks were no longer precise and a project was established in an attempt to provide a usable check. (In floating point (A + B) + C is not necessarily the same as A + (B + C) <i>i.e.</i> the + operation is not associative.) Before long, however, it was recognized that error rates with transistor machines was not an issue; they either worked correctly or did not work at all. Consequently, the idea of sum checks was abandoned. The initial matrix package proved a very useful system testing tool as it was able to generate lengthy performance checks well before more formal test packages which were subsequently developed. </p><p>There is a legend that the KDF9 was developed as project KD9 (Kidsgrove Development 9) and that the 'F' in its designation was contributed by the then chairman after a long and tedious discussion on what to name the machine at launch—"I don’t care if you call it the <a href="/wiki/Fuck" title="Fuck">F—</a>". The truth is more mundane: the name was chosen essentially at random by a marketing manager.<sup id="cite_ref-KDF9_NAME_11-0" class="reference"><a href="#cite_note-KDF9_NAME-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> (See also <a href="/wiki/KDF8" class="mw-redirect" title="KDF8">KDF8</a> for the parallel development and use of a commercially oriented computer.) </p><p>The EGDON operating system was so named because one was going to <a href="/wiki/UKAEA" class="mw-redirect" title="UKAEA">UKAEA</a> <a href="/wiki/Winfrith" title="Winfrith">Winfrith</a>: in <a href="/wiki/Thomas_Hardy" title="Thomas Hardy">Thomas Hardy</a>'s book <i><a href="/wiki/The_Return_of_the_Native" title="The Return of the Native">The Return of the Native</a></i> Winfrith Heath is called <a href="/wiki/Egdon_Heath" title="Egdon Heath">Egdon Heath</a>. EGDON Fortran was called EGTRAN.<sup id="cite_ref-KDF9_NAME_11-1" class="reference"><a href="#cite_note-KDF9_NAME-11"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Eldon was so named because <a href="/wiki/Leeds_University" class="mw-redirect" title="Leeds University">Leeds University</a>'s computer was located in a converted Eldon chapel. </p> <div class="mw-heading mw-heading2"><h2 id="Physical">Physical</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=6" title="Edit section: Physical"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>The machine weighed more than 10,300 pounds (5.2 short tons; 4.7 t). Control desk with interruption typewriter 300 lb (136 kg), main store and input/output control unit 3,500 (1,587 kg), arithmetic and main control unit 3,500 (1,587 kg), power supply unit 3,000 (1,360 kg).<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Notes">Notes</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=7" title="Edit section: Notes"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-NB_Sum_check-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-NB_Sum_check_10-0">^</a></b></span> <span class="reference-text">The sum check equally well guarded against programming errors, in the event that some or all of a matrix was inadvertently overwritten.</span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=8" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239543626"><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-hansard-19670306-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-hansard-19670306_1-0">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFRoberts1967" class="citation web cs1">Roberts, Goronwy (1967-03-06). <a rel="nofollow" class="external text" href="https://api.parliament.uk/historic-hansard/written-answers/1967/mar/06/computers">"Computers"</a>. <i><a href="/wiki/Hansard" title="Hansard">Parliamentary Debates (Hansard)</a></i>. HC<span class="reference-accessdate">. Retrieved <span class="nowrap">2017-07-08</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Parliamentary+Debates+%28Hansard%29&rft.atitle=Computers&rft.date=1967-03-06&rft.aulast=Roberts&rft.aufirst=Goronwy&rft_id=https%3A%2F%2Fapi.parliament.uk%2Fhistoric-hansard%2Fwritten-answers%2F1967%2Fmar%2F06%2Fcomputers&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><a rel="nofollow" class="external text" href="http://www.cs.man.ac.uk/CCS/res/res18.htm#c">"The KDF9 Computer - 30 Years On"</a></span> </li> <li id="cite_note-EE_1961-3"><span class="mw-cite-backlink"><b><a href="#cite_ref-EE_1961_3-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://www.ourcomputerheritage.org/KDF9_Flier.pdf"><i>English Electric KDF9: Very high speed data processing system for Commerce, Industry, Science</i></a> <span class="cs1-format">(PDF)</span> (Product flyer). <a href="/wiki/English_Electric" title="English Electric">English Electric</a>. c. 1961. Publication No. DP/103. 096320WP/RP0961. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200727143037/http://www.ourcomputerheritage.org/KDF9_Flier.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2020-07-27<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-07-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=English+Electric+KDF9%3A+Very+high+speed+data+processing+system+for+Commerce%2C+Industry%2C+Science&rft.pub=English+Electric&rft_id=http%3A%2F%2Fwww.ourcomputerheritage.org%2FKDF9_Flier.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFDavid_Holdsworth2009–10" class="citation web cs1">David Holdsworth (Winter 2009–10). <a rel="nofollow" class="external text" href="http://www.cs.man.ac.uk/CCS/res/res49.htm#e">"KDF9 Time Sharing: Eldon 2 is not EGDON!"</a>. <i>Computer RESURRECTION –  issue 49</i>. <a href="/wiki/Computer_Conservation_Society" title="Computer Conservation Society">Computer Conservation Society</a><span class="reference-accessdate">. Retrieved <span class="nowrap">2010-10-03</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Computer+RESURRECTION+%26ndash%3B%26%2332%3B+issue+49&rft.atitle=KDF9+Time+Sharing%3A+Eldon+2+is+not+EGDON%21&rft.ssn=winter&rft.date=2009%2F2010&rft.au=David+Holdsworth&rft_id=http%3A%2F%2Fwww.cs.man.ac.uk%2FCCS%2Fres%2Fres49.htm%23e&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> <li id="cite_note-5"><span class="mw-cite-backlink"><b><a href="#cite_ref-5">^</a></b></span> <span class="reference-text">Curnow, H. J. and Wichman, B. A. "<a rel="nofollow" class="external text" href="https://www.webarchive.org.uk/wayback/archive/20130303230703/http://www.roylongbottom.org.uk/whetstone.pdf">A Synthetic Benchmark</a>" <i>Computer Journal</i>, Volume 19, Issue 1, February 1976., pp. 43–49.</span> </li> <li id="cite_note-crit1-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-crit1_6-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWeiss" class="citation web cs1">Weiss, Alan. <a rel="nofollow" class="external text" href="http://www.johnloomis.org/NiosII/dhrystone/ECLDhrystoneWhitePaper.pdf">"Dhrystone Benchmark: History, Analysis, "Scores" and Recommendations"</a> <span class="cs1-format">(PDF)</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Dhrystone+Benchmark%3A+History%2C+Analysis%2C+%22Scores%22+and+Recommendations&rft.aulast=Weiss&rft.aufirst=Alan&rft_id=http%3A%2F%2Fwww.johnloomis.org%2FNiosII%2Fdhrystone%2FECLDhrystoneWhitePaper.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> <li id="cite_note-EE_Director-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-EE_Director_7-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation book cs1"><a rel="nofollow" class="external text" href="http://sw.ccs.bcs.org/KDF9/directorManuals/20090803114911646.pdf"><i>Director - Manual</i></a> <span class="cs1-format">(PDF)</span> (Flowchart). <a href="/wiki/English_Electric" title="English Electric">English Electric</a>. c. 1960s. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200727222921/http://sw.ccs.bcs.org/KDF9/directorManuals/20090803114911646.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2020-07-27<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-07-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Director+-+Manual&rft.pub=English+Electric&rft_id=http%3A%2F%2Fsw.ccs.bcs.org%2FKDF9%2FdirectorManuals%2F20090803114911646.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span> (NB. Mentions the term "syllabic octal".)</span> </li> <li id="cite_note-Beard_1997-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-Beard_1997_8-0">^</a></b></span> <span class="reference-text"><span class="anchor" id="Beard-1997"></span><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFBeard1997" class="citation magazine cs1">Beard, Bob (Autumn 1997) [1996-10-01]. <a rel="nofollow" class="external text" href="http://www.cs.man.ac.uk/CCS/Archive/Resurrection/pdf/res18.pdf">"The KDF9 Computer — 30 Years On"</a> <span class="cs1-format">(PDF)</span>. <i><a href="/wiki/Resurrection_(magazine)" class="mw-redirect" title="Resurrection (magazine)">Resurrection</a> - The Bulletin of the Computer Conservation Society</i>. No. 18. <a href="/wiki/Computer_Conservation_Society" title="Computer Conservation Society">Computer Conservation Society</a> (CCS). pp. 7–15 [9, 11]. <a href="/wiki/ISSN_(identifier)" class="mw-redirect" title="ISSN (identifier)">ISSN</a> <a rel="nofollow" class="external text" href="https://search.worldcat.org/issn/0958-7403">0958-7403</a>. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200727140754/http://www.cs.man.ac.uk/CCS/Archive/Resurrection/pdf/res18.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2020-07-27<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-07-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=article&rft.jtitle=Resurrection+-+The+Bulletin+of+the+Computer+Conservation+Society&rft.atitle=The+KDF9+Computer+%E2%80%94+30+Years+On&rft.ssn=fall&rft.issue=18&rft.pages=7-15+9%2C+11&rft.date=1997&rft.issn=0958-7403&rft.aulast=Beard&rft.aufirst=Bob&rft_id=http%3A%2F%2Fwww.cs.man.ac.uk%2FCCS%2FArchive%2FResurrection%2Fpdf%2Fres18.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span> <a rel="nofollow" class="external autonumber" href="https://web.archive.org/web/20200427075718/http://www.cs.man.ac.uk/CCS/res/res18.htm#c">[1]</a> (NB. This is an edited version of a talk given to North West Group of the Society at the Museum of Science and Industry, Manchester, UK on 1996-10-01. It mentions the term "slob" and "slob-octal" as equivalent to "syllabic octal".)</span> </li> <li id="cite_note-CCS_2009-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-CCS_2009_9-0">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.ourcomputerheritage.org/ccs-n2x2.pdf">"Architecture of the English Electric KDF9 computer"</a> <span class="cs1-format">(PDF)</span>. Version 1. <a href="/wiki/Computer_Conservation_Society" title="Computer Conservation Society">Computer Conservation Society</a> (CCS). September 2009. CCS-N4X2. <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200404195007/http://www.ourcomputerheritage.org/ccs-n2x2.pdf">Archived</a> <span class="cs1-format">(PDF)</span> from the original on 2020-04-04<span class="reference-accessdate">. Retrieved <span class="nowrap">2020-07-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Architecture+of+the+English+Electric+KDF9+computer.&rft.series=Version+1&rft.pub=Computer+Conservation+Society+%28CCS%29&rft.date=2009-09&rft_id=http%3A%2F%2Fwww.ourcomputerheritage.org%2Fccs-n2x2.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span> (NB. Refers to Beard's 1997 <a href="#Beard-1997">article</a>.)</span> </li> <li id="cite_note-KDF9_NAME-11"><span class="mw-cite-backlink">^ <a href="#cite_ref-KDF9_NAME_11-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-KDF9_NAME_11-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/#About">"(re)Introducing the KDF9"</a>. <i>www.findlayw.plus.com</i><span class="reference-accessdate">. Retrieved <span class="nowrap">2020-12-27</span></span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.findlayw.plus.com&rft.atitle=%28re%29Introducing+the+KDF9&rft_id=http%3A%2F%2Fwww.findlayw.plus.com%2FKDF9%2F%23About&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="http://www.computerhistory.org/brochures/d-f/english-electric/">"English Electric | Selling the Computer Revolution | Computer History Museum"</a>. <i>www.computerhistory.org</i>. p. 27.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=www.computerhistory.org&rft.atitle=English+Electric+%7C+Selling+the+Computer+Revolution+%7C+Computer+History+Museum&rft.pages=27&rft_id=http%3A%2F%2Fwww.computerhistory.org%2Fbrochures%2Fd-f%2Fenglish-electric%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AEnglish+Electric+KDF9" class="Z3988"></span></span> </li> </ol></div></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=English_Electric_KDF9&action=edit&section=9" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20English%20Electric%20KDF9.pdf">The English Electric KDF9</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20Hardware%20of%20the%20KDF9.pdf">The Hardware of the KDF9</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20Software%20of%20the%20KDF9.pdf">The Software of the KDF9</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20KDF9%20and%20Benchmarking.pdf">The KDF9 and Benchmarking</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20KDF9-a%20Bibliography.pdf">The KDF9: a Bibliography</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/The%20KDF9%20Character%20Codes.pdf">The KDF9 character codes</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/#Emulator">ee9</a>, a KDF9 emulator written in <a href="/wiki/Gnu_Ada" class="mw-redirect" title="Gnu Ada">GNU Ada</a></li> <li><a rel="nofollow" class="external text" href="http://www.findlayw.plus.com/KDF9/#PSK">PASKAL</a>, a KDF9 Pascal cross compiler written in Pascal</li> <li><a rel="nofollow" class="external text" href="http://www.ourcomputerheritage.org/ccs-n2x1.pdf">Delivery List and applications for the English Electric KDF9</a> <a rel="nofollow" class="external text" href="https://web.archive.org/web/20200404194953/http://www.ourcomputerheritage.org/ccs-n2x1.pdf">Archived</a> 2020-04-04 at the <a href="/wiki/Wayback_Machine" title="Wayback Machine">Wayback Machine</a></li> <li><a rel="nofollow" class="external text" href="http://www.cs.ncl.ac.uk/research/pubs/articles/papers/427.pdf">History of KDF9 Algol compiler</a></li> <li><a rel="nofollow" class="external text" href="http://www.cs.ncl.ac.uk/research/pubs/books/papers/124.pdf">The Whetstone KDF9 Algol Translator</a></li> <li><a rel="nofollow" class="external text" href="http://www.computerconservationsociety.org/resurrection/res04.htm">Some KDF9 Algol compiler anecdotes</a></li> <li><a rel="nofollow" class="external text" href="http://www.cs.ncl.ac.uk/research/pubs/trNN/papers/34.pdf">Presentation on KDF9 Algol on visit from Dijkstra</a></li> <li><a rel="nofollow" class="external text" href="http://history.cs.ncl.ac.uk/anniversaries/40th/images/kdf9/08.html">KDF9 Nest</a> (images)</li> <li><a rel="nofollow" class="external text" href="http://history.dcs.ed.ac.uk/archive/languages/atlas-autocode/imp9.imp.txt">Source Code for KDF9 port of Atlas Autocode compiler</a></li></ul> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline ol,.mw-parser-output .hlist.inline ul,.mw-parser-output .hlist dl dl,.mw-parser-output .hlist dl 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title="Template talk:ICL hardware"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:ICL_hardware" title="Special:EditPage/Template:ICL hardware"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="International_Computers_Limited_(ICL)_1968-2002795" style="font-size:114%;margin:0 4em"><a href="/wiki/International_Computers_Limited" title="International Computers Limited">International Computers Limited</a> (ICL) 1968-2002</div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Predecessor <a href="/wiki/Mainframe_computer" title="Mainframe computer">mainframes</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/LEO_(computer)" title="LEO (computer)">LEO I</a></li> <li><a href="/wiki/ICT_1301" title="ICT 1301">ICT 1301</a></li> <li><a href="/w/index.php?title=ICT_1501&action=edit&redlink=1" class="new" title="ICT 1501 (page does not exist)">ICT 1501</a></li> <li><a href="/wiki/Elliott_803" title="Elliott 803">Elliott 803</a></li> <li><a href="/wiki/English_Electric_KDF8" title="English Electric KDF8">KDF8</a></li> <li><a class="mw-selflink selflink">KDF9</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/English_Electric_System_4" title="English Electric System 4">English Electric System 4 series</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/10</a></li> <li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/30</a></li> <li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/50</a></li> <li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/70</a></li> <li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/72</a></li> <li><a href="/wiki/English_Electric_System_4" title="English Electric System 4">System 4/75</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ICT_1900_series" title="ICT 1900 series">ICT 1900 series</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>1901</li> <li>1901A</li> <li>1901S</li> <li>1901T</li> <li>1902</li> <li>1902A</li> <li>1902S</li> <li>1902T</li> <li>1903</li> <li>1903A</li> <li>1903S</li> <li>1903T</li> <li>1904</li> <li>1904A</li> <li>1904E</li> <li>1904F</li> <li>1904S</li> <li>1905</li> <li>1905E</li> <li>1905F</li> <li>1906</li> <li>1906A</li> <li>1906E</li> <li>1906F</li> <li>1906S</li> <li>1907</li> <li>1907E</li> <li>1907F</li> <li>1908</li> <li>1909</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">ICL 2900 Series</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2950</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2955</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2956</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2960</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2966</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2970</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2972</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2976</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2980</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2982</a></li> <li><a href="/wiki/ICL_2900_Series" title="ICL 2900 Series">2988</a></li> <li><a href="/wiki/Content_Addressable_File_Store" title="Content Addressable File Store">CAFS</a></li> <li><a href="/wiki/ICL_Distributed_Array_Processor" title="ICL Distributed Array Processor">DAP</a></li> <li><a href="/wiki/Order_code_processor" class="mw-redirect" title="Order code processor">OCP</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ICL_Series_39" title="ICL Series 39">ICL Series 39</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ICL_Series_39" title="ICL Series 39">Level 30</a></li> <li><a href="/wiki/ICL_Series_39" title="ICL Series 39">Level 50</a></li> <li><a href="/wiki/ICL_Series_39" title="ICL Series 39">Level 60</a></li> <li><a href="/wiki/ICL_Series_39" title="ICL Series 39">Level 80</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Minicomputer" title="Minicomputer">Minicomputers</a><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:ICL_minicomputers" title="Category:ICL minicomputers">category</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ICL_2903" class="mw-redirect" title="ICL 2903">2903</a></li> <li><a href="/wiki/ICL_2904" class="mw-redirect" title="ICL 2904">2904</a></li> <li><a href="/wiki/ICL_2905" class="mw-redirect" title="ICL 2905">2905</a></li> <li><a href="/wiki/ICL_ME29" class="mw-redirect" title="ICL ME29">ME29</a></li> <li><a href="/wiki/System_Ten" class="mw-redirect" title="System Ten">System Ten</a></li> <li><a href="/wiki/System_25" class="mw-redirect" title="System 25">System 25</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Workstation" title="Workstation">Workstations</a><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:ICL_workstations" title="Category:ICL workstations">category</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ICL_7500_series" title="ICL 7500 series">7502</a></li> <li><a href="/wiki/ICL_7500_series" title="ICL 7500 series">7503</a></li> <li><a href="/wiki/ICL_7500_series" title="ICL 7500 series">7561</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 20</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 100</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 200</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 300</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 400</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 500</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 3000</a></li> <li><a href="/wiki/ICL_DRS" title="ICL DRS">DRS 6000</a></li> <li><a href="/wiki/PERQ" title="PERQ">PERQ</a></li> <li><a href="/wiki/One_Per_Desk" title="One Per Desk">One Per Desk</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Operating_system" title="Operating system">Operating systems</a><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:ICL_operating_systems" title="Category:ICL operating systems">category</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ICL_VME" title="ICL VME">OpenVME</a></li> <li><a href="/wiki/ICL_VME" title="ICL VME">VME</a></li> <li><a href="/wiki/ICL_VME" title="ICL VME">VME/B</a></li> <li><a href="/wiki/ICL_VME" title="ICL VME">VME/K</a></li> <li><a href="/wiki/SuperNova_(operating_system)" class="mw-redirect" title="SuperNova (operating system)">superNova</a></li> <li><a href="/wiki/ICL_CME" class="mw-redirect" title="ICL CME">CME</a></li> <li><a href="/wiki/ICL_Direct_Machine_Environment" title="ICL Direct Machine Environment">DME</a></li> <li><a href="/wiki/ICL_Transaction_Machine_Environment" class="mw-redirect" title="ICL Transaction Machine Environment">TME</a></li> <li><a href="/wiki/Executive_(operating_system)" class="mw-redirect" title="Executive (operating system)">Executive</a></li> <li><a href="/wiki/GEORGE_(operating_system)" title="GEORGE (operating system)">GEORGE</a></li> <li><a href="/wiki/MAXIMOP" class="mw-redirect" title="MAXIMOP">MAXIMOP</a></li> <li><a href="/wiki/MINIMOP" title="MINIMOP">MINIMOP</a></li> <li><a href="/wiki/J_(operating_system)" class="mw-redirect" title="J (operating system)">J</a></li> <li><a href="/wiki/MultiJob" class="mw-redirect" title="MultiJob">MultiJob</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Programming_language" title="Programming language">Programming languages</a><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <a href="/wiki/Category:ICL_programming_languages" title="Category:ICL programming languages">category</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/PLAN_(computer_language)" class="mw-redirect" title="PLAN (computer language)">PLAN</a></li> <li><a href="/wiki/Fortran" title="Fortran">Fortran</a></li> <li><a href="/wiki/ALGOL" title="ALGOL">ALGOL</a> 60</li> <li><a href="/wiki/Southampton_BASIC_System" title="Southampton BASIC System">SOBS</a></li> <li><a href="/wiki/COBOL" title="COBOL">COBOL</a></li> <li><a href="/wiki/JEAN" title="JEAN">JEAN</a></li> <li><a href="/wiki/C_(programming_language)" title="C (programming language)">C</a></li> <li><a href="/wiki/Pascal_(programming_language)" title="Pascal (programming language)">Pascal</a></li> <li><a href="/wiki/S3_(programming_language)" title="S3 (programming language)">S3</a></li> <li><a href="/wiki/SCL_(job_control_language)" class="mw-redirect" title="SCL (job control language)">SCL</a></li> <li><a href="/wiki/SFL_(programming_language)" class="mw-redirect" title="SFL (programming language)">SFL</a></li> <li><a href="/wiki/ICL_VME#Quickbuild" title="ICL VME">ApplicationMaster</a></li> <li><a href="/wiki/ReportMaster" class="mw-redirect" title="ReportMaster">ReportMaster</a></li> <li><a href="/wiki/IBM_RPG" title="IBM RPG">RPG</a></li> <li><a href="/wiki/DAP_FORTRAN" title="DAP FORTRAN">DAP FORTRAN</a></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="ALGOL445" style="padding:3px"><table class="nowraplinks hlist mw-collapsible mw-collapsed navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:ALGOL_programming" title="Template:ALGOL programming"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:ALGOL_programming" title="Template talk:ALGOL programming"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:ALGOL_programming" title="Special:EditPage/Template:ALGOL programming"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="ALGOL445" style="font-size:114%;margin:0 4em"><a href="/wiki/ALGOL" title="ALGOL">ALGOL</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Programming_language_implementation" title="Programming language implementation">Implementations</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Technical_standard" title="Technical standard">Technical<br />standards</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ALGOL_58" title="ALGOL 58">ALGOL 58</a></li> <li><a href="/wiki/ALGOL_60" title="ALGOL 60">ALGOL 60</a></li> <li><a href="/wiki/ALGOL_68" title="ALGOL 68">ALGOL 68</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Dialect_(computing)" class="mw-redirect" title="Dialect (computing)">Dialects</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>ABC ALGOL</li> <li><a href="/wiki/ALCOR" title="ALCOR">ALCOR</a></li> <li><a href="/wiki/ALGO" title="ALGO">ALGO</a></li> <li><a href="/wiki/ALGOL_68C" title="ALGOL 68C">ALGOL 68C</a></li> <li><a href="/wiki/ALGOL_68-R" title="ALGOL 68-R">ALGOL 68-R</a></li> <li><a href="/wiki/ALGOL_68RS" title="ALGOL 68RS">ALGOL 68RS</a> (<a href="/wiki/ELLA_(programming_language)" title="ELLA (programming language)">ELLA</a>)</li> <li><a href="/wiki/ALGOL_68S" title="ALGOL 68S">ALGOL 68S</a></li> <li><a href="/wiki/ALGOL_N" title="ALGOL N">ALGOL N</a></li> <li><a href="/wiki/ALGOL_W" title="ALGOL W">ALGOL W</a></li> <li><a href="/wiki/ALGOL_X" class="mw-redirect" title="ALGOL X">ALGOL X</a></li> <li><a href="/wiki/Atlas_Autocode" title="Atlas Autocode">Atlas Autocode</a> (<a href="/wiki/Edinburgh_IMP" title="Edinburgh IMP">Edinburgh IMP</a>)</li> <li><a href="/wiki/Burroughs_Large_Systems#ALGOL" title="Burroughs Large Systems">Burroughs ALGOL</a></li> <li><a href="/wiki/CORAL" title="CORAL">CORAL</a> 66</li> <li><a href="/wiki/Dartmouth_ALGOL_30" title="Dartmouth ALGOL 30">Dartmouth ALGOL 30</a></li> <li><a href="/wiki/DASK" title="DASK">DASK</a> ALGOL</li> <li><a href="/wiki/DG/L" title="DG/L">DG/L</a></li> <li><a href="/wiki/Elliott_ALGOL" title="Elliott ALGOL">Elliott ALGOL</a></li> <li><a href="/wiki/Executive_Systems_Problem_Oriented_Language" title="Executive Systems Problem Oriented Language">Executive Systems Problem Oriented Language</a> (ESPOL) → New Executive Programming Language (<a href="/wiki/NEWP" title="NEWP">NEWP</a>)</li> <li><a href="/wiki/FLACC" title="FLACC">FLACC</a></li> <li><a href="/wiki/IMP_(programming_language)" title="IMP (programming language)">IMP</a></li> <li><a href="/wiki/JOVIAL" title="JOVIAL">JOVIAL</a></li> <li><a class="mw-selflink selflink">Kidsgrove</a> Algol</li> <li><a href="/wiki/MAD_(programming_language)" title="MAD (programming language)">MAD</a></li> <li><a href="/wiki/Mary_(programming_language)" title="Mary (programming language)">Mary</a></li> <li><a href="/wiki/NELIAC" title="NELIAC">NELIAC</a></li> <li><a href="/wiki/RTL/2" title="RTL/2">RTL/2</a></li> <li><a href="/wiki/S-algol" title="S-algol">S-algol</a>, <a href="/wiki/PS-algol" title="PS-algol">PS-algol</a>, <a href="/wiki/Napier88" title="Napier88">Napier88</a></li> <li><a href="/wiki/Simula" title="Simula">Simula</a></li> <li>Small Machine ALGOL Like Language (<a href="/wiki/SMALL" title="SMALL">SMALL</a>)</li> <li><a href="/wiki/SMIL_(computer)" title="SMIL (computer)">SMIL</a> ALGOL</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Formalism_(philosophy_of_mathematics)" title="Formalism (philosophy of mathematics)">Formalisms</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Jensen%27s_device" title="Jensen's device">Jensen's device</a></li> <li><a href="/wiki/Van_Wijngaarden_grammar" title="Van Wijngaarden grammar">Van Wijngaarden grammar</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Community_of_practice" title="Community of practice">Community</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Organizations</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Professional_association" title="Professional association">Professional<br />associations</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/ALCOR" title="ALCOR">ALCOR</a> Group</li> <li><a href="/wiki/Association_for_Computing_Machinery" title="Association for Computing Machinery">Association for Computing Machinery</a> (ACM)</li> <li><a href="/wiki/BSI_Group" title="BSI Group">BSI Group</a></li> <li><a href="/wiki/GOST" title="GOST">Euro-Asian Council for Standardization, Metrology and Certification</a> (EASC)</li> <li><a href="/wiki/International_Federation_for_Information_Processing" title="International Federation for Information Processing">International Federation for Information Processing</a> (IFIP) <a href="/wiki/IFIP_Working_Group_2.1" title="IFIP Working Group 2.1">IFIP Working Group 2.1</a></li> <li><a href="/wiki/Gesellschaft_f%C3%BCr_Angewandte_Mathematik_und_Mechanik" title="Gesellschaft für Angewandte Mathematik und Mechanik">Society of Applied Mathematics and Mechanics</a> (GAMM)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Business</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Burroughs_Corporation" title="Burroughs Corporation">Burroughs Corporation</a></li> <li><a href="/wiki/Elliott_Brothers_(computer_company)" title="Elliott Brothers (computer company)">Elliott Brothers</a></li> <li><a href="/wiki/Regnecentralen" title="Regnecentralen">Regnecentralen</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Education</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Case_Western_Reserve_University" title="Case Western Reserve University">Case Institute of Technology</a></li> <li><a href="/wiki/University_of_Edinburgh" title="University of Edinburgh">University of Edinburgh</a></li> <li><a href="/wiki/University_of_St_Andrews" title="University of St Andrews">University of St Andrews</a></li> <li><a href="/wiki/Manchester_University" class="mw-redirect" title="Manchester University">Manchester University</a></li> <li><a href="/wiki/Massachusetts_Institute_of_Technology" title="Massachusetts Institute of Technology">Massachusetts Institute of Technology</a> (MIT)</li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Government</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Royal_Radar_Establishment" title="Royal Radar Establishment">Royal Radar Establishment</a> (RRE)</li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">People</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ALGOL_58" title="ALGOL 58">ALGOL 58</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/John_Backus" title="John Backus">John Backus</a></li> <li><a href="/wiki/Friedrich_L._Bauer" title="Friedrich L. Bauer">Friedrich L. Bauer</a></li> <li><a href="/wiki/Hermann_Bottenbruch" title="Hermann Bottenbruch">Hermann Bottenbruch</a></li> <li><a href="/wiki/Charles_Katz" title="Charles Katz">Charles Katz</a></li> <li><a href="/wiki/Alan_Perlis" title="Alan Perlis">Alan Perlis</a></li> <li><a href="/wiki/Heinz_Rutishauser" title="Heinz Rutishauser">Heinz Rutishauser</a></li> <li><a href="/wiki/Klaus_Samelson" title="Klaus Samelson">Klaus Samelson</a></li> <li><a href="/wiki/Joseph_Henry_Wegstein" title="Joseph Henry Wegstein">Joseph Henry Wegstein</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/MAD_(programming_language)" title="MAD (programming language)">MAD</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bruce_Arden" title="Bruce Arden">Bruce Arden</a></li> <li><a href="/wiki/Bernard_Galler" title="Bernard Galler">Bernard Galler</a></li> <li><a href="/wiki/Robert_M._Graham_(computer_scientist)" title="Robert M. Graham (computer scientist)">Robert M. Graham</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ALGOL_60" title="ALGOL 60">ALGOL 60</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><td colspan="2" class="navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Backus^</li> <li><a href="/wiki/Roland_Carl_Backhouse" title="Roland Carl Backhouse">Roland Carl Backhouse</a></li> <li>Bauer^</li> <li><a href="/wiki/Richard_Bird_(computer_scientist)" title="Richard Bird (computer scientist)">Richard Bird</a></li> <li><a href="/wiki/Stephen_R._Bourne" title="Stephen R. Bourne">Stephen R. Bourne</a></li> <li><a href="/wiki/Edsger_W._Dijkstra" title="Edsger W. Dijkstra">Edsger W. Dijkstra</a></li> <li><a href="/wiki/Andrey_Ershov" class="mw-redirect" title="Andrey Ershov">Andrey Ershov</a></li> <li><a href="/wiki/Robert_W._Floyd" title="Robert W. Floyd">Robert W. Floyd</a></li> <li><a href="/wiki/Jeremy_Gibbons" title="Jeremy Gibbons">Jeremy Gibbons</a></li> <li>Julien Green</li> <li><a href="/wiki/David_Gries" title="David Gries">David Gries</a></li> <li><a href="/wiki/Eric_Hehner" title="Eric Hehner">Eric Hehner</a></li> <li><a href="/wiki/Tony_Hoare" title="Tony Hoare">Tony Hoare</a></li> <li><a href="/wiki/J%C3%B8rn_Jensen" title="Jørn Jensen">Jørn Jensen</a></li> <li>Katz^</li> <li><a href="/wiki/Peter_Landin" title="Peter Landin">Peter Landin</a></li> <li><a href="/wiki/Tom_Maibaum" title="Tom Maibaum">Tom Maibaum</a></li> <li><a href="/wiki/Conor_McBride" title="Conor McBride">Conor McBride</a></li> <li><a href="/wiki/John_McCarthy_(computer_scientist)" title="John McCarthy (computer scientist)">John McCarthy</a></li> <li><a href="/wiki/Carroll_Morgan_(computer_scientist)" title="Carroll Morgan (computer scientist)">Carroll Morgan</a></li> <li><a href="/wiki/Peter_Naur" title="Peter Naur">Peter Naur</a></li> <li><a href="/wiki/Maurice_Nivat" title="Maurice Nivat">Maurice Nivat</a></li> <li><a href="/wiki/John_E._L._Peck" title="John E. L. Peck">John E. L. Peck</a></li> <li>Perlis^</li> <li><a href="/wiki/Brian_Randell" title="Brian Randell">Brian Randell</a></li> <li>Rutishauser^</li> <li>Samelson^</li> <li><a href="/wiki/Jacob_T._Schwartz" title="Jacob T. Schwartz">Jacob T. Schwartz</a></li> <li><a href="/wiki/Micha_Sharir" title="Micha Sharir">Micha Sharir</a></li> <li><a href="/wiki/David_Turner_(computer_scientist)" title="David Turner (computer scientist)">David Turner</a></li> <li><a href="/wiki/Bernard_Vauquois" title="Bernard Vauquois">Bernard Vauquois</a></li> <li><a href="/wiki/Eiiti_Wada" title="Eiiti Wada">Eiiti Wada</a></li> <li>Wegstein^</li> <li><a href="/wiki/Adriaan_van_Wijngaarden" title="Adriaan van Wijngaarden">Adriaan van Wijngaarden</a></li> <li><a href="/wiki/Mike_Woodger" title="Mike Woodger">Mike Woodger</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Simula" title="Simula">Simula</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Ole-Johan_Dahl" title="Ole-Johan Dahl">Ole-Johan Dahl</a></li> <li><a href="/wiki/Kristen_Nygaard" title="Kristen Nygaard">Kristen Nygaard</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/ALGOL_68" title="ALGOL 68">ALGOL 68</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Bauer^</li> <li><a href="/wiki/Susan_G._Bond" title="Susan G. Bond">Susan G. Bond</a></li> <li>Bourne^</li> <li><a href="/wiki/Robert_Dewar" title="Robert Dewar">Robert Dewar</a></li> <li>Dijkstra^</li> <li><a href="https://de.wikipedia.org/wiki/Gerhard_Goos" class="extiw" title="de:Gerhard Goos">Gerhard Goos</a></li> <li><a href="/wiki/Michael_Guy" title="Michael Guy">Michael Guy</a></li> <li>Hoare^</li> <li><a href="/wiki/Cornelis_H._A._Koster" title="Cornelis H. A. Koster">Cornelis H. A. Koster</a></li> <li><a href="/wiki/Peter_Landin" title="Peter Landin">Peter Landin</a></li> <li><a href="/wiki/Charles_H._Lindsey" title="Charles H. Lindsey">Charles H. Lindsey</a></li> <li><a href="/wiki/Barry_J._Mailloux" title="Barry J. Mailloux">Barry J. Mailloux</a></li> <li>McCarthy^</li> <li><a href="/wiki/Lambert_Meertens" title="Lambert Meertens">Lambert Meertens</a></li> <li>Naur^</li> <li>Peck^</li> <li><a href="/wiki/Willem_van_der_Poel" title="Willem van der Poel">Willem van der Poel</a></li> <li>Randell^</li> <li><a href="/wiki/Douglas_T._Ross" title="Douglas T. Ross">Douglas T. Ross</a></li> <li>Samelson^</li> <li><a href="/wiki/Michel_Sintzoff" title="Michel Sintzoff">Michel Sintzoff</a></li> <li>van Wijngaarden^</li> <li><a href="/wiki/Niklaus_Wirth" title="Niklaus Wirth">Niklaus Wirth</a></li> <li>Woodger^</li> <li><a href="/wiki/Philip_Woodward" title="Philip Woodward">Philip Woodward</a></li> <li><a href="/wiki/Nobuo_Yoneda" title="Nobuo Yoneda">Nobuo Yoneda</a></li></ul> </div></td></tr></tbody></table><div> <ul><li><a href="/wiki/Hal_Abelson" title="Hal Abelson">Hal Abelson</a></li> <li><a href="/wiki/John_Barnes_(computer_scientist)" title="John Barnes (computer scientist)">John Barnes</a></li> <li><a href="/wiki/Tony_Brooker" title="Tony Brooker">Tony Brooker</a></li> <li><a href="/wiki/Ron_Morrison" title="Ron Morrison">Ron Morrison</a></li> <li><a href="/wiki/Peter_O%27Hearn" title="Peter O'Hearn">Peter O'Hearn</a></li> <li><a href="/wiki/John_C._Reynolds" title="John C. Reynolds">John C. Reynolds</a></li></ul></div></td></tr></tbody></table><div> <ul><li><i><a href="/wiki/ALGOL_Bulletin" title="ALGOL Bulletin">ALGOL Bulletin</a></i></li></ul></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Comparison</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <li><a href="/wiki/ALGOL_58#ALGOL_58's_influence_on_ALGOL_60" title="ALGOL 58">ALGOL 58 influence on ALGOL 60</a></li> <li><a href="/wiki/ALGOL_68#Comparisons_with_other_languages" title="ALGOL 68">ALGOL 68 to other languages</a></li> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><b>^ = full name and link in prior ALGOL version above</b><br /><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Category:Algol_programming_language_family" title="Category:Algol programming language family">Category: ALGOL</a></b> <span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Category:ALGOL_60" title="Category:ALGOL 60">Category: ALGOL 60</a></b></li></ul> </div></td></tr></tbody></table></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?useformat=desktop&type=1x1&usesul3=0" alt="" width="1" height="1" style="border: none; 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