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funding. Standingford and
Thompson wrote a report to the Lyons' board recommending that Lyons should acquire or build a computer to meet their business needs. The board agreed that, as a first step, Lyons would provide Hartree and Wilkes with £2,500 for the EDSAC project, and would also provide them with the services of a Lyons electrical engineer, Ernest Lenaerts. EDSAC was completed and ran its first program in May 1949.
374:, and so on. One of its early tasks was the elaboration of daily orders, which were phoned in every afternoon by the shops and used to calculate the overnight production requirements, assembly instructions, delivery schedules, invoices, costings, and management reports. This was the first instance of an integrated management information system. The LEO project was also a pioneer in
40:
280:, a radar engineer and research student at Cambridge, as team leader for the project. Lenaerts returned to Lyons to work on the project, and Wilkes provided training for Lyons' engineer Derek Hemy, who would be responsible for writing LEO's programs. On 15 February 1951 the computer, carrying out a simple test program, was shown to
264:
On their return to the UK, Standingford and
Thompson visited Hartree and Wilkes in Cambridge and were favourably impressed with their technical expertise and vision. Hartree and Wilkes estimated that EDSAC was 12–18 months from completion, but said that this interval could be shortened by additional
485:
notes that before LEO I the company already had a proven, industry-leading system using clerks that gave it "near-real-time management information on more or less all aspects of its business", and that no jobs were lost when the system was computerized. In addition, LEO Computers lost money on many
430:
One of the features that LEO III shared with many computers of the day was a loudspeaker connected to the central processor via a divide-by-100 circuit and an amplifier which enabled operators to tell whether a program was looping by the distinctive sound it made. Another quirk was that many
502:
project. In
November 2021, to coincide with the 70th anniversary of the first successful full program run on LEO I, the project released a film about the history of LEO, which went on to win Video of the Year in the Association of British Science Writers Awards in July 2022.
287:. The first business application to be run on LEO was Bakery Valuations, which computed the costs of ingredients used in bread and cakes. This was successfully run on 5 September 1951, and LEO took over Bakery Valuations calculations completely on 29–30 November 1951.
232:
was one of the UK's leading catering and food manufacturing companies in the first half of the 20th century. In 1947, two of its senior managers, Oliver
Standingford and Raymond Thompson, were sent to the United States to look at new business methods developed during
308:
LEO I's clock speed was 500 kHz, with most instructions taking about 1.5 ms to execute. To be useful for business applications, the computer had to be able to handle a number of data streams, input and output, simultaneously. Therefore, its chief designer,
454:
and this led to the breaking up of the team that had inspired LEO computers. The company continued to build the LEO III, and went on to build the faster LEO 360 and even faster LEO 326 models, which had been designed by the LEO team before the takeover.
378:: in 1956, Lyons started doing the payroll calculations for Ford UK and others on the LEO I machine. The success of this led to the company dedicating one of its LEO II machines to bureau services. Later, the system was used for scientific computations as well.
245:, the first general-purpose electronic computer. Standingford and Thompson saw the potential of computers to help solve the problem of administering a major business enterprise. They also learned from Goldstine that, back in the UK,
268:
Following the successful completion of EDSAC, the Lyons board agreed to start the construction of their own machine, expanding on the EDSAC design. The LEO computer room, which took up around 2,500 square feet of floor space, was at
497:
for their project aiming to bring together, preserve, archive and digitise a range of LEO Computers artefacts, and documents. The Centre's museum gallery has an area dedicated to LEO, and as of 2021 they are also working on a LEO
205:
LEO I ran its first business application in 1951. In 1954 Lyons formed LEO Computers Ltd to market LEO I and its successors LEO II and LEO III to other companies. LEO Computers eventually became part of
1440:
which is intended to be a comprehensive reference to archive, museum and media holdings and references to LEO computers, and individuals associated with them, updated periodically by
1080:
458:
English
Electric LEO Computers (EEL) (1963), then English Electric Leo Marconi (EELM) (1964), later English Electric Computers (EEC) (1967), eventually merged with
210:(EEL), (EELM), then English Electric Computers (EEC), where the same team developed the faster LEO 360 and even faster LEO 326 models. It then passed to
2337:
887:
474:
development centre. At least one modern emulator has been developed which can run some original LEO III software on a modern server. ICL was bought by
2317:
841:
1543:"Developing LEO: The world's first business computer", documents from the papers of John Simmons, Modern Records Centre, University of Warwick
293:
was employed in 1952 as the first female programmer to work on LEO, and as such she is recognized as the first female commercial programmer.
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17:
412:
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1477:
1494:, University of Minnesota. Pinkerton describes his work on LEO computers. In this context he discusses the British computer firms
1343:
442:, until 1981, primarily producing telephone bills. They were kept running using parts from redundant LEOs purchased by the GPO.
389:
In 1954, with the decision to proceed with LEO II and interest from other commercial companies, Lyons formed LEO Computers Ltd.
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and punches, and a 100-line-per-minute tabulator. Later, other devices, including magnetic tape, were added. Its ultrasonic
2153:
806:
1387:
Land, Frank (1999). "A Historical
Analysis of Implementing IS at J. Lyons." In Currie, W. G.; Galliers, R. D., editors.
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intermittent faults were due to faulty connectors and could be temporarily fixed by briskly strumming the card handles.
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The Lyons machine was christened Lyons
Electronic Office, or LEO. On the recommendation of Wilkes, Lyons recruited
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408:"Master program" operating system, which allowed concurrent running of as many as 12 application programs.
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1484:, who worked on the first LEO computer and was the first woman to become a commercial computer programmer
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The first in the series, the LEO I, was the first computer used for commercial business applications.
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mainframes running LEO programs, using an emulator written in ICL 2960 microcode at the
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1919:
1554:
1495:
1436:
1359:
1350:
Land, F. F. (2000). "The First
Business Computer: A Case Study in User-Driven Automation".
1447:
1081:"Centre for Computing History and LEO Computers Society win Heritage Lottery Fund support"
8:
1515:, The Guildhall conference for business leaders, London, 2001. Archived in February 2012.
846:
776:
435:
397:
1366:
Caminer, D. T. (1997). "LEO and its
Applications: The Beginning of Business Computing".
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434:
Some LEO III machines purchased in the mid-to-late 1960s remained in commercial use at
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346:), was four times as large as that of EDSAC. The systems analysis was carried out by
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127:
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Lyons used LEO I initially for valuation jobs, but its role was extended to include
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63:
945:
Berry, F. J. (1 February 1959). "Intercode, a
Simplified Coding Scheme for AMOS".
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Land, F. F., (1997). LEO, the First Business Computer: A Personal Experience. In
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779:, archives and manuscripts catalogue, the British Library. Retrieved 2 June 2020
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1952:
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Caminer, D. T. (2003). "Behind the Curtain at LEO: A Personal Reminiscence".
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198:
197:. Its construction was overseen by Oliver Standingford, Raymond Thompson and
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A Computer Called LEO: Lyons Tea Shops and the World's First Office Computer
1133:
LEO: The Story of the World's First Business Computer – Computing History UK
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Five files of archive material on the LEO Computer patent are held at the
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2014:
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BBC Radio 4 series about early computers, 2002; programme 1 is about LEO
1999:
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1201:
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818:
728:"Women in Computing: a British Perspective – Google Arts & Culture"
379:
270:
1237:
Caminer, D. T., Aris, J. B. B., Hermon, P. M. R., Land, F. F. (1996).
999:
learned a language called Cleo which was similar in many ways to Cobol
481:
Whether its investment in LEO actually benefited J. Lyons is unclear.
2004:
401:
371:
1518:
1287:. Washington:Joseph Henry Press. Chapter 5: LEO the Lyons Computer.
382:
staff used a LEO I before the Met Office bought its own computer, a
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and can be accessed through the British Library Archives catalogue.
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1989:
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1979:
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343:
180:
119:
1380:
Hendry, J. (1988). "The Teashop Computer Manufacturer: J. Lyons".
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Land, F. F. (1996). "Systems Analysis for Business Applications".
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LEO: the incredible story of the world's first business computer
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along with LEO Computers Society were awarded funding from the
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The Staffordshire University Computing Futures Museum LEO Page
39:
2231:
2220:
1550:"The Evolution of Design in a series of Computers, LEO I-III"
1487:
555:"70 years ago, 'computer for business' LEO ran first biz app"
424:
254:
242:
194:
155:
1448:
LEO Magnetic Data Tape Collection at The ICL Computer Museum
1285:
Electronic Brains: stories from the dawn of the computer age
1258:
Carmichael, H., editor (1996). An ICL Anthology, Chapter 6:
253:
were actually building another such machine, the pioneering
2236:
2086:
1240:
User-Driven Innovation: The World’s First Business Computer
411:
Users of LEO computers programmed in two coding languages:
1341:
Aris, J. B. B. (2000). "Inventing Systems Engineering".
1327:
Aris, J. B. B. (1996). "Systems Design – Then and Now".
863:"The story of LEO – the World's First Business Computer"
1600:"LEO: the story of the world's first business computer"
842:"How a chain of tea shops kickstarted the computer age"
825:. Office of Naval Research, Dept. of the Navy. p.
1478:
How a cake company pioneered the first office computer
1199:
313:, designed the machine to have multiple input/output
1304:
In the Beginning: Recollections of Software Pioneers
486:
of its sales because of unrealistically low prices.
1357:Caminer, D. T. (1958), "...And How to Avoid Them".
317:. In the first instance, these were linked to fast
221:LEO series computers were still in use until 1981.
392:The first LEO III was completed in 1961; it was a
1470:, National Archive for the History of Computing,
1463:LEO Artefacts at the Centre for Computing History
1354:, Vol. 22, No. 3, July–September, pp. 16–26.
668:
2294:
1488:Oral history interview with John M. M. Pinkerton
819:Research, United States Office of Naval (1953).
662:
190:The prototype LEO I was modelled closely on the
1421:(Has information on the LEO III character set.)
1347:, Vol. 22, No. 3, July–September, pp. 4–15
1154:"We Won Video of the Year! – Computing History"
617:"Meet LEO, the world's first business computer"
807:World's First Business Computer, LEO, Turns 60
695:"Bletchley Park celebrates women in computing"
466:(ICL) in 1968. In the 1980s, there were still
353:
147:and punches, and a 100 line a minute tabulator
1632:
1539:BBC Radio 4 series, 2016; programme about LEO
423:: Clear Language for Expressing Orders), the
224:
1200:Caminer, D. T.; Aris, J. B.; Hermon, P. M.;
2338:University of Cambridge Computer Laboratory
1050:
450:In 1963, LEO Computers Ltd was merged into
1639:
1625:
1059:"The Case for the First Business Computer"
867:Warwick University - Modern records centre
840:Williams, Christopher (10 November 2011).
241:who was one of the original developers of
38:
1567:
1547:
1525:(2002); at David Lawrence's Lyons website
1389:Rethinking Management Information Systems
44:Logo of LEO Computers Ltd 1954 until 1963
1458:LEO Paperwork at The ICL Computer Museum
1453:LEO Artefacts at The ICL Computer Museum
1110:Centre for Computing History LEO VR blog
915:
913:
888:"History of computing at the Met Office"
839:
357:
1536:Hidden Histories of the Information Age
1513:Business Computing: the Second 50 Years
1375:IEEE Annals of the History of Computing
1352:IEEE Annals of the History of Computing
1344:IEEE Annals of the History of Computing
1078:
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822:A survey of automatic digital computers
692:
396:machine with a 13.2 μs cycle time
362:A circuit board from a LEO III computer
14:
2318:Computer-related introductions in 1951
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1548:Pinkerton, J. M. M. (1 January 1961).
1398:
1040:
1021:
669:computingheritage (5 September 2013),
460:International Computers and Tabulators
333:, with 2K (2048) 35-bit words (i.e., 8
1620:
1377:, Vol. 25, No. 2, April–June, pp3–13.
1265:
1228:ICL: A Business and Technical History
953:(2). AMOS - Ferranti Mark I*: 55–58.
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1085:Centre for Computing History website
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1188:. Wokingham: Hasler Publishing Co.
553:Speed, Richard (30 November 2021).
24:
1384:, Vol. 29, No. 8, pp. 73–102.
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1098:
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693:Douglas, Ian (11 September 2013).
445:
321:readers and punches, fast punched
143:readers and punches, fast punched
25:
2354:
1523:LEO – The First Business Computer
1425:
1411:from the original on 16 July 2018
1407:. The Early Days of Hexadecimal.
860:
753:"Mary Coombs – Computing History"
606:
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2019:
2018:
1967:
1966:
1701:English Electric System 4 series
1610:The Centre for Computing History
1519:J. Lyons & Co. LEO Computers
1472:University of Manchester Library
1315:Three Case Studies in Automation
1186:LEO: The First Business Computer
1079:McGerty, Lisa (8 October 2018).
592:. Hasler. pp. 84, 86, 228.
589:LEO: The First Business Computer
1648:International Computers Limited
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1057:Pelling, Nick (26 March 2002).
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464:International Computers Limited
212:International Computers Limited
109:2K (2048) 35-bit words (i.e., 8
1529:BBC Science: Electronic Brains
1262:, Laidlaw Hicks, Surbiton, UK.
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635:
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438:Telephones, the forerunner of
13:
1:
1044:LEO III software preservation
1011:LEO Computers Society website
518:
513:List of vacuum-tube computers
237:. During the visit, they met
1521:. Extract from Peter Bird's
1504:International Computers Ltd.
1399:Savard, John J. G. (2018) .
1226:Campbell-Kelly, M., (1989).
672:Mary Coombs shares her story
491:Centre for Computing History
18:English Electric Leo Marconi
7:
1320:Simmons, J. R. M., (1962).
1158:www.computinghistory.org.uk
757:www.computinghistory.org.uk
506:
354:Applications and successors
83:; 73 years ago
10:
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225:Origins and initial design
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2013:
1961:
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1492:Charles Babbage Institute
1480:BBC video interview with
1270:, London: Fourth Estate,
732:Google Cultural Institute
586:Bird, Peter John (1994).
462:(ICT) and others to form
419:type language; and CLEO (
303:
161:
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134:
105:
95:
77:
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55:Lyons Electronic Office I
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37:
1586:"David Caminer obituary"
1468:LEO Computers Collection
1266:Ferry, Georgina (2003),
452:English Electric Company
404:and was controlled by a
208:English Electric Company
179:) was a series of early
2333:Supply chain management
2308:ICL mainframe computers
2303:Early British computers
1393:Oxford University Press
1106:"History in the Making"
921:"Leo III installations"
794:23 January 2012 at the
641:Ferry (2003), Chapter 4
540:Ferry (2003), Chapter 3
531:Ferry (2003), Chapter 2
259:University of Cambridge
177:Lyons Electronic Office
363:
2313:Vacuum tube computers
2194:Programming languages
1569:10.1093/comjnl/4.1.42
1432:LEO Computers Society
1401:"Computer Arithmetic"
1308:IEEE Computer Society
1025:THE DME LEO DME STORY
1022:Morgan, Tony (2012),
959:10.1093/comjnl/2.2.55
925:LEO Computers Society
495:Heritage Lottery Fund
361:
214:(ICL) and ultimately
27:1951 British computer
1555:The Computer Journal
1496:J. Lyons and Company
1391:, pp. 310–325.
1368:The Computer Journal
1360:The Computer Journal
1338:, Summer issue 1996.
1331:, Summer issue 1996.
1324:, MacDonald, London.
1322:LEO and the Managers
981:"Creative Computing"
947:The Computer Journal
2323:History of software
1612:. 30 November 2021.
1310:, Los Alamitos, CA.
1041:Holdsworth, David,
847:The Daily Telegraph
777:LEO Computer Patent
699:The Daily Telegraph
656:The British Library
398:ferrite core memory
183:systems created by
34:
1370:, Vol. 40, No. 10.
1283:Hally, M. (2005).
986:Creative Computing
898:on 9 December 2010
892:Met Office website
364:
329:based on tanks of
285:Princess Elizabeth
126:based on tanks of
32:
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2267:ApplicationMaster
2102:Operating systems
1306:, pages 134–153.
809:, TechWeek Europe
623:. 9 November 2018
327:delay-line memory
257:computer, at the
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136:Removable storage
124:delay-line memory
16:(Redirected from
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230:J. Lyons and Co.
203:J. Lyons and Co.
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1650:(ICL) 1968-2002
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1594:. 24 June 2008.
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415:, a low-level
355:
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311:John Pinkerton
305:
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278:John Pinkerton
251:Maurice Wilkes
226:
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51:Also known as
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2272:ReportMaster
2092:One Per Desk
2015:Workstations
1665:
1656:Predecessor
1603:
1589:
1562:(1): 42–46.
1559:
1553:
1535:
1522:
1512:
1435:
1413:. Retrieved
1404:
1388:
1381:
1374:
1367:
1358:
1351:
1342:
1336:Resurrection
1335:
1329:Resurrection
1328:
1321:
1314:
1303:
1300:Glass, R. L.
1284:
1267:
1259:
1238:
1227:
1205:
1185:
1161:. Retrieved
1157:
1148:
1137:, retrieved
1132:
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1114:. Retrieved
1109:
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1088:. Retrieved
1084:
1074:
1062:. Retrieved
1052:
1043:
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1024:
1017:
1006:
998:
991:. Retrieved
984:
975:
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946:
940:
928:. Retrieved
924:
902:26 September
900:. Retrieved
896:the original
891:
882:
870:. Retrieved
866:
856:
845:
835:
821:
814:
802:
784:
772:
760:. Retrieved
756:
747:
735:. Retrieved
731:
722:
710:. Retrieved
698:
688:
677:, retrieved
671:
664:
655:
646:
637:
625:. Retrieved
620:
588:
564:. Retrieved
560:The Register
558:
536:
527:
488:
483:Nick Pelling
480:
457:
449:
433:
429:
427:equivalent.
410:
406:multitasking
391:
388:
365:
323:card readers
307:
295:
289:
275:
267:
263:
235:World War II
228:
220:
189:
176:
172:
170:
145:card readers
78:Release date
60:Manufacturer
29:
2328:Outsourcing
2282:DAP FORTRAN
1734:System 4/75
1729:System 4/72
1724:System 4/70
1719:System 4/50
1714:System 4/30
1709:System 4/10
1681:Elliott 803
1482:Mary Coombs
1434:. Includes
1245:McGraw-Hill
1210:McGraw-Hill
1202:Land, F. F.
1182:Bird, P. J.
930:30 November
627:30 November
566:30 November
394:solid-state
386:, in 1959.
376:outsourcing
291:Mary Coombs
152:Predecessor
2297:Categories
2000:System Ten
1658:mainframes
1442:Frank Land
1302:, editor.
1243:. London:
1230:. Oxford:
1116:30 January
1090:30 January
519:References
380:Met Office
319:paper tape
271:Cadby Hall
141:paper tape
70:Generation
2159:Executive
2139:superNova
2005:System 25
1578:0010-4620
1509:About LEO
1405:quadibloc
967:0010-4620
707:0307-1235
675:, YouTube
478:in 1990.
417:assembler
413:Intercode
400:. It was
372:inventory
344:kilobytes
192:Cambridge
162:Successor
120:kilobytes
2203:category
2184:MultiJob
2111:category
2082:DRS 6000
2077:DRS 3000
2024:category
1972:category
1953:Level 80
1948:Level 60
1943:Level 50
1938:Level 30
1676:ICT 1501
1671:ICT 1301
1437:LEOPEDIA
1409:Archived
1204:(1998).
1184:(1994).
872:7 August
792:Archived
507:See also
472:Dalkeith
468:ICL 2900
181:computer
2216:Fortran
2174:MINIMOP
2169:MAXIMOP
2119:OpenVME
2072:DRS 500
2067:DRS 400
2062:DRS 300
2057:DRS 200
2052:DRS 100
1605:YouTube
1511:– From
1415:16 July
1163:16 July
1139:16 July
1064:25 June
762:26 July
737:26 July
712:26 July
679:26 July
476:Fujitsu
421:acronym
368:payroll
338:⁄
331:mercury
315:buffers
216:Fujitsu
128:mercury
114:⁄
86: (
2247:Pascal
2164:GEORGE
2047:DRS 20
1576:
1502:, and
1291:
1274:
1251:
1216:
1192:
993:4 June
989:. 1985
965:
705:
596:
304:Design
165:LEO II
106:Memory
2232:COBOL
2221:ALGOL
2134:VME/K
2129:VME/B
1832:1907F
1829:1907E
1823:1906S
1820:1906F
1817:1906E
1814:1906A
1808:1905F
1805:1905E
1799:1904S
1796:1904F
1793:1904E
1790:1904A
1784:1903T
1781:1903S
1778:1903A
1772:1902T
1769:1902S
1766:1902A
1760:1901T
1757:1901S
1754:1901A
1666:LEO I
1029:(PDF)
425:COBOL
255:EDSAC
243:ENIAC
195:EDSAC
156:EDSAC
33:LEO I
2237:JEAN
2227:SOBS
2211:PLAN
2087:PERQ
2042:7561
2037:7503
2032:7502
1995:ME29
1990:2905
1985:2904
1980:2903
1910:CAFS
1905:2988
1900:2982
1895:2980
1890:2976
1885:2972
1880:2970
1875:2966
1870:2960
1865:2956
1860:2955
1855:2950
1838:1909
1835:1908
1826:1907
1811:1906
1802:1905
1787:1904
1775:1903
1763:1902
1751:1901
1691:KDF9
1686:KDF8
1574:ISSN
1417:2018
1289:ISBN
1272:ISBN
1249:ISBN
1214:ISBN
1190:ISBN
1165:2022
1141:2022
1118:2021
1092:2021
1066:2013
995:2021
963:ISSN
932:2021
904:2010
874:2018
764:2018
739:2018
714:2018
703:ISSN
681:2018
629:2021
594:ISBN
568:2021
249:and
171:The
88:1951
81:1951
2277:RPG
2262:SFL
2257:SCL
2154:TME
2149:DME
2144:CME
2124:VME
1920:OCP
1915:DAP
1564:doi
1260:LEO
955:doi
436:GPO
282:HRH
201:of
173:LEO
97:CPU
2299::
2252:S3
2223:60
1608:.
1602:.
1588:.
1572:.
1558:.
1552:.
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1490:,
1403:.
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1156:.
1108:.
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716:.
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631:.
602:.
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340:4
336:3
175:(
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116:4
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Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.
