Think Piece

What Makes a PC? Thoughts on Computing Platforms, Standards, and Compatibility

James Sumner University of Manchester Editor: Nathan Ensmenger

In May 2006, Apple Computer launched yet another existing entities. The hardware was assembled mostly from memorable advertising campaign. Humorous personifica- non-IBM standard parts, while an operating system, famous- tions of ‘‘a Mac’’ (home-loving, casual, straightforward) and ly, was sought from the fledgling , which licensed ‘‘a PC’’ (deskbound, formal, rather unreliable) reflect and adapted an existing system, which in turn was heavily a perceived division in technical quality and underlying informed by the well-established CP/M. Unlike Apple, ethos. While this may seem to resemble other consumer however, IBM swiftly lost gatekeeper status over its emerging duopoly cases—Sony versus Nintendo, Pepsi versus Coke— platform, as a legion of PC ‘‘clone’’ producers emerged.2 the ‘‘PC’’ represents no one product, corporation, or interest Early microcomputing culture was characterized by a pro- group. The commercials’ comical concrete examples support liferation of other machine-oriented platforms, often aimed a surprisingly abstract argument. at home users. Contemporaneously with Apple, the estab- Until recently, Apple positioned itself as a necessary lished electronics firms Commodore and Tandy Radio Shack alternative to IBM, the commercial computing behemoth introduced formulations of the that long which released the modern PC’s technical ancestor in 1981, so endured, sustained by enthusiastic user communities and appropriating the name ‘‘personal computer’’ to itself.1 IBM vigorous software development cultures. In the UK, my has lost this defining role, and the rising generation of users is particular field of study, American producers competed with unaware of any ‘‘IBM-compatible’’ heritage. A proposed numerous small manufacturers’ independent specifications. successor term is ‘‘Wintel,’’ highlighting the surviving tangible This culture is often characterized as a Babel of incompat- identifiers, -originated microprocessors, and Microsoft ible platforms that the IBM PC, offering all the advantages of Windows operating systems. Yet this is no basis for distinction. a consensus standard, rapidly swept out of existence.3 Apple’s ‘‘Get a Mac’’ campaign stresses that all its machines Certainly, however, that 1981 machine did not represent feature Intel processors and will run Windows XP or Vista a concerted push to overrun other personal-computer makers’ beside Apple’s OS X. markets—these were, after all, high-turnover, retail-oriented This apparently paradoxical strategy—simultaneous dis- markets, far from IBM’s core concerns. The platform was missal and assimilation of PC norms—is nothing new. Taking intended, probably, as a kite in the wind. It grew beyond thelongviewprovidesuswithsomevaluablein- expectation not because buyers wanted IBM, sights into the role of systems and standards in computer but because traditional IBM buyers increasingly wanted technology, and offers direction for future research. ; thus it was never truly IBM’s to control. ‘‘Mac’’ and ‘‘PC’’ have never been standards. They are In the large-computing era, when IBM consistently held best understood as platforms: constellations of standards, over 70 percent of the US market, its competitors typically conventions, and expectations that influence the nature depended on niche adaptation, serving markets too small or and behavior of hardware, software, producers, users, and esoteric for the giant’s attention. This strategy might as easily mediators. Standards may invite stark choices between be social or geopolitical as technical: whereas Control Data acceptance or rejection, as in the iconic case of the 4 ft. 3 Corp. specialized in fast-processing machines,4 European 8.5 in. railway gauge. Computer technologies’ ‘‘universal producers such as ICL, Philips, and Olivetti capitalized on machine’’ characteristics, by contrast, offer paths of partial local knowledge and national flagship status. Similarly, assimilation, emulation, and translation. Platforms, more- following the release of the IBM PC, many manufacturers over, are partially rhetorical constructs whose boundaries sought to respond with a compatible but crucially different may be contested and redefined. machine. This only becomes obvious when we consider Apple built its tremendous early growth on the Apple II a computer as part of a user system, rather than the sum of its microcomputer platform, which appeared seemingly from processor and software specifications. The first conspicuous- nowhere in 1977. Mass-produced computer systems, of ly successful ‘‘clone,’’ specified by (1983), was no course, do not appear from nowhere. They rely on pre- clone in physical form, but a portable device inspired by pre- existing capital, parts, code concepts, production capacity, PC machines such as the Osborne-1. and distribution networks. The remarkable achievement of ‘‘Platforms’’ need not bespecified at the machinelevel, and Apple’s tiny staff was to co-ordinate all these into a viable may cut across each other. ’s CP/M operating product; to establish that product (‘‘the computer,’’ but in system provided a common software and information in- fact the platform) as deserving of attention; and to identify terchange platform for a variety of business-oriented hard- Apple as its only begetter, arbiter of its development and ware, enduring well into the 1980s. The Web, today, provides guarantor of its future validity. a common basis for development in online communication IBM’s original Personal Computer, released into a well- across many applications. Moreover, compatibility need not developed market in 1981, was likewise a constellation of continued on p. 87

88 IEEE Annals of the History of Computing Published by the IEEE Computer Society 1058-6180/07/$25.00 G 2007 IEEE continued from p. 88 The actual eclipse of these platforms in in- operate rigorously at a technical level. Microsoft’s ternational context awaits serious investigation. Basic dialect, its principal product before the IBM In Britain, affordable PC-compatibles arrived in deal, was licensed for each major platform (Com- offices (principally via the indigenous volume modore’s, Apple’s, and Radio Shack’s). The ma- electronics manufacturer Amstrad) from 1986. chines’ specifics usually made the direct transfer of Yet first-generation users around this time gener- code impossible; yet the commonalities were close allyupgradednottoPCsbuttonewplatforms enough for amateur users to make the appropriate from Commodore and Atari. My subjective translations themselves. recollection is that the convention of diverse A further lesson is the need to look beyond the competing hardware platforms did not wilt, in US. In the European markets that responded first the UK, until the arrival of cheap machines based to the microprocessor-driven computer—homes, on the 486 processor around 1993. small business, pre-university education—the What pushed the PC into the traditional niche IBM-compatibles were long understood as one areas was not standardization but economics: the among several possibilities at the high-cost end of logic of mass production drove retail prices to a broad market;5 ‘‘standardization’’ most often a level at which buying a PC made sense. Generic suggested CP/M, not IBM, into the mid-1980s. and nicheless, PCs are increasingly underdeter- Certainly, historians should pay due attention to mined in style and function, and sometimes even the defining role of Commodore, subject of in form (hence the plaintive comment of the arecentpopularaccountthatforcefullydecries Apple campaign’s PC figure: ‘‘The rest of me’s in the Apple-centric nature of much existing litera- some other boxes…’’). At the same time, white- ture.6 Though US-based, Commodore sold heavily collar norms continue to inform, for instance, into Europe, dominating in particular the exten- , and the mismatch with home sive German home market at a time when Apple’s users’ priorities creates a nagging tension. ‘‘Get machines were beyond most purchasers’ means. a Mac’’ is merely the latest campaign to exploit Commodore’s opening of a home-user market the principle of compatible design, marrying the through price-cutting, it seems, was inspired by technicalities of the PC to the Mac’s established the British firm Sinclair’s success in promoting social and cultural base. limited machines on a price-point design philos- ophy.7 The unique result for Britain was a home References and notes market carved largely between Commodore and 1. Most notably through the thinly veiled totalitarian Sinclair, with some smaller niche suppliers re- references in the iconic launch maining viable over a decade or more. advertisement (1984). More subtly, ‘‘Think Putting these insights together allows us to Different’’ (1997–2002) plays on IBM’s venerable understand the rationale behind a variety of corporate motto ‘‘THINK!’’ heterogeneous developments. In Britain, for in- 2. The legal/technical acrobatics of the reverse- stance, the Grundy NewBrain (1983) was a tiny engineering process involved are elegantly handheld device, yet ran CP/M with memory summarized in P. Ceruzzi, A History of Modern expandable to the strictly ‘‘business’’ value of two Computing, MIT Press, 2003, pp. 277-280. megabytes. Acorn’s BBC Microcomputer (1981), 3. For instance: G. Laing, Digital Retro, Ilex, 2004, endorsed by the national public broadcaster’s pp. 6-7, 186. computer literacy initiative, used the same 6502 4. M. Campbell-Kelly and W. Aspray, processorastheearlyCommodoresandApples,but Computer: A History of the Information Machine, wasdesignedtointerfacewithasecondprocessorto Westview, 2004, pp. 121-122. run CP/M, Unix-like systems, or systems not yet 5. See for instance the threefold division of ‘‘Low cost,’’ designed.Acorn’ssuccessindefininganeducation- ‘‘Medium-priced,’’ and ‘‘Business’’ in H. Varley and I. based niche inspired another British producer, Graham, The Personal Computer Handbook,Pan, Research Machines (RM), to introduce the Nimbus PC (1985): loosely following IBM-inspired archi- 1983, pp. 182-187. tecture and running a customized version of MS- 6. B. Bagnall, On the Edge: The Spectacular Rise and DOS, the device featured BBC Micro emulation and Fall of Commodore, Variant, 2005. could interface with various educational periph- 7. Ibid., p. 152; L. Haddon, ‘‘The Home Computer: The erals. Such machines could be eccentric in terms of Making of a Consumer Electronic,’’ Science as formalhardwarespecification—Nimbuswasoneof Culture,vol.2,1988,pp.7-51. very few microcomputers ever built around Intel’s 80186 processor—and might seem uncompeti- Contact James Sumner about this article at tively priced. Their validity and (sometimes tran- [email protected]. sient) viability were established at the level of user Contact department editor Nathan Ensmenger community orientation and support. at [email protected].

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