Replying more generally on the question of counterfactuals. Thanks to Andy, Evan, and others who replied on this. I will have a look at the papers they mention. In one of my more obscure publications, "Technology's Other Storytellers: Science Fiction as History of Technology," I made the argument that SF writers and historians of technology are both in the business of producing historical narratives in which technology plays a role in changing the course of historical development. The difference is that historians tell a story of what "actually" happened and usually stop their narratives before the time the book is finished, whereas SF writers trace a different chain of events and often follow that chain after the time the book is finished (though by the time the book is read the point of departure from our actual history is inevitably in the past - making SF a form of historical fiction). http://www.tomandmaria.com/Tom/Writing/TechnologysOtherStorytellersDRAFT.pdf I go on to argue that the counterfactual alternative, while usually implicit in the history of technology, is essential to making the historical writing analytical rather than just (as those from outside the field sometimes see it) a list of things that happened arranged end to end. Historical causes are always overdetermined, and there are always too many details to put in a narrative. By picking details and highlighting causes the historian is suggesting that, had those details been different or those particular causes lacking, events would have moved in a different direction. It would be fascinating to see more discussion of counterfactual history of computing. At the risk of being branded a technological determinist, my sense is that there was a lot less flexibility with respect to end points than with respect to the paths to get to them. Particular combinations of technology and business model make sense, and the question is more which firms and platforms can discover the winning model first and execute it best. For example, by the early 1980s the vision of a universal network that would allow email, home shopping, telecommunting, etc. was well established. Over the next decade efforts like OSI, viewdata services, AOL and other online services, smart set top boxes, etc. were funded to try to deliver on it. The contingent part is that it was the Internet/Web combo that blossomed to fill that need, meaning that features such as micropayments for online publishers were missing and email wasn't authenticated to a sender but, on the positive side, the network was open to different services and users. Those details all had profound influences on how online practices and businesses developed, e.g. the destruction of the newspaper industry. With respect to the evolution of personal computing, it's hard for me to imagine the big picture going particularly differently post-1980 if one assumes progress in hardware continuing at roughly the same pace. In the first half of the 1980s GUIs and advanced operating systems overtaxed available hardware, meaning that only expensive but still sluggish workstations could support them. These could only be supported by niche high value applications like engineering, and publishing where the graphical capabilities were crucial. So as some responses suggested, it was probably inevitable that the mass market platform of the mid-1980s would be a simple and efficient text-based OS that didn't impose too much overhead between applications and hardware. Hansen mentioned the Apple II GS - perhaps the real counterfactual is if Apple had introduced this in 1983 instead of Lisa, not crippled its performance, and then evolved it through multiple generations of compatible hardware. By the late 1980s hardware was getting cheaper and faster, GUIs were imposing less of a performance penalty, and mass market machines could hold enough RAM to make multitasking practical. The direction of the future was clear, but the path there over the next decade wasn't. Remember that NT ran on Mips, Alpha, and PowerPC as well as Intel. OS/2 ran windows 3.X apps and also supported multiple platforms. Apple, IBM and others were supporting a common hardware platform, and were supposed to produce Taligent as a common OS. Apple allowed clones, then banned them. There were efforts to standardize Unix. Linux made a push for the desktop. MacOS faltered badly in the late 1990s. Windows 9X was startlingly successful bridging users from the DOS-based 16 bit Windows 3.X to the industrial grade Windows NT underpinnings of Windows 2000 and XP. Intel fell way behind RISC performance but rallied with the later Pentiums. So if you go back and read the play by plays in the industry literature it was a time of incredible uncertainty and rapid change in which all kinds of grand plans and alliance fell apart with amazing speed and key products shipped years late. The other question, as mentioned earlier on the list, was open vs. closed business models for PC producers. Versus 1990 PC makers Apple had its own custom floppy drives, hardware, different processors, OS, keyboard connectors, etc. and users had only one place to by Macs. PC purchases could choose from thousands of suppliers, who were just buying components from thousands of Asian producers and screwing them into a case. In an era of rapid change the PC ecosystem drove down costs and encouraged rapid innovation in components such as graphics cards. This almost drove Apple out of business, and after Jobs returned caused it to retreat to a niche of high priced, good looking premium products. On the other hand, let's step back to look at where things settled down. Apple gave up on having a hardware platform of its own, bit by bit, finishing up with the processor shift to Intel in 2006. On the PC side, Intel integrated everything that was on half a dozen expansion cards into a couple of chips, meaning that PCs are pretty much standard. The shift to laptops and all in one designs means that PCs and Macs are both basically closed internally but can be expanded externally. Both platforms have stable, 64-bit operating systems with equivalent features. Both OSes are, technologically, a complete departure from 1980s PC systems - Windows being NT which is based on Culter's minicomputer projects, OSX being (as discussed by Hansen et al) NeXT Step which in turn is BSD Unix. So the two models have converged in the same place - I liked the BMW vs Ford remark attributed to Jobs in an earlier post, but while BMW is more profitable than Ford (particularly on a per-vehicle basis) either can sell you a fast, comfortable vehicle that will functionally do everything you need. The difference are design, branding, and social cachet. Here's what I mean about the convergence of end points: if the 1990s had gone completely differently and Linux had wiped out Windows on the desktop, or everyone was running OS/2 on Alpha, or Taligent on PowerPC had swept all before it, by about 2005 there probably wouldn't be very much difference. People would still have rock sold, modern operating systems running on cheap fast hardware that was shrinking into laptops or all in one systems. So I can definitely sell a narrative where a different platform dominates early-2000s personal computing. I just tend to feel that it would be running on commodity hardware, be integrated into stylish compact boxes, and do basically what Windows XP and OS X do. I suppose there are some significant differences, for example whether Microsoft makes money on each PC, but that matters more to Microsoft than to users. I can see plenty of paths not taken, but they all seem to lead to the same place. Is this a failure of my imagination? Tom