Unfinished Revolution - The Innovation of PCs in the 1970s

Man has created the myth of “the computer” in his own image,
or one of them: cold, immaculate, sterile “scientific,” oppressive.
Some people flee this image. Others, drawn toward it, have
joined the cold-sterile-oppressive cult, and propagate it like a faith.
Many are still about this mischief, making people do things rigidly
and saying it is the computer’s fault.

—Ted Nelson, Computer Lib (1974), 2

Introduction (1)

On the cover of the January 1975 issue of Popular Electronics appears a picture of the first personal computer, the Altair 8800.[1]

Fig.1 January 1975, Popular Electronics, features the Altair 8800, the first personal computer.

The Altair hardly looks like today’s personal computer. Sold at $395, it had only a toggle-switched LED front panel, and did not come with a keyboard or a monitor.[2]Most consumers bought the Altair as mail order kits and assembled them chip by chip. The assembly was not a simple task even for electronics hobbyists, and some of them never successfully got their Altairs to function.[3]

Ed Roberts, the creator of the Altair, did not expect much either. Since the late 1960s, Roberts’ small electronics company, Micro Instrumentation Telemetry System (MITS), had manufactured several products, including a programmable calculator in a kit form.[4] However, none of these products succeeded, and some failed disastrously. At the margin of bankruptcy, Roberts thought his last chance might be the idea of a minicomputer with the newly available processor, Intel 8080, sold at $75 apiece.[5] Meanwhile, Leslie Solomon and Arthur Salsberg, editors of Popular Electronics, had been looking for a better machine than the one offered by their competitor, Radio Electronics, since July 1974. They saw the possibility of beating the Mark-8, which was priced around $1,000 (roughly equivalent to $3,360 in 2002 dollars) yet based on the relatively slower Intel 8008 processor. Through their personal network, Solomon and Salsberg contacted Roberts.[6] They managed to convince Roberts that if a new model were ready by the following January, they would be able to generate enough sales to keep MITS in business.

No one was aware of the history they were making. The Altair 8800 computer kit that Roberts produced became the first affordable personal computer and an overnight success. According to computer historian Frank Delaney:

Roberts estimated if he got lucky he would sell enough computer kits to keep his business afloat while he looked for other revenue sources, possibly 200 kits in a year. . . . in one day they sold 200 computers over the phone. People sent checks in sight unseen—completely on the faith they would some day receive their kit in the mail. . . . Some fanatics even drove to Albuquerque [the headquarter of MITS] and camped out in the parking lot to wait for their kits.[7]

With only 256 bytes of memory, the Altair was by no means functionally comparable to its contemporaries—the IBM time-sharing computers. Owning an Altair was more like having a new toy than gaining any substantial power of computing. Why, then, were these engineers, or hobbyists as they preferred be called, so eager to own personal computers?[8]

Words like “dream” and “imagining” repeatedly appeared in the advocacy of new ways of computing in the 1970s. For instance, idealist Theodor Nelson (known as Ted Nelson) published Computer Lib/Dream Machines in 1974, even before the personal computer came into existence. Pleading: “You can and must understand computers now,” Nelson demanded “new freedoms through computer screens.”[9] In his article entitled “The Impossible Dream” in the first issue of Byte, the editor of this popular computer magazine wrote: “Wouldn’t it be neat to have a computer all one’s own without being as rich as Croesus?”[10] In addition to the affordability that Byte’s editor dreamed about, the imagination of the People's Computer Company (PCC) went further. On the cover of PCC Newpaper, March 1975, it was not just a computer, but a comfortable computing environment integrated with a nice sofa and surrounding plants.

Fig.2 Cover of the People's Computer Company Newspaper, March 1975. The person in this advertisement is imagining a pleaassant home computer environment.

1. Gregg Williams and Mark Welch, “A Microcomputing Timeline,” Byte, September 1985.
2. LED is the abbreviation of light-emitting diode, an electronic device that lights up when electricity passing through. The Random House Personal Computer Dictionary (1991), s.v. “LED.” As for comparative dollar values, according to the online Dollar Conversion Calculator created by Professor Robert Sahr of the Oregon State University Political Science Department, one 1975 dollar is equivalent to $3.36 in 2002 dollars. Therefore, the price of Altair 8800 in 1975 was roughly the equivalent of $1,327 in 2002 dollars—not much different from that of today’s personal computers. See “CJR Dollar Conversion Calculator,” Columbia Journalism Review, 2002, <http://www.cjr.org/resources/inflater.asp> (1 March 2003).
3. Paul Freiberger and Michael Swaine, Fire in the Valley: The Making of the Personal Computer (Berkeley, California: Osborne/McGraw-Hill, 1984), 31.
4. Ibid., 29.
5. Ibid., 31.
6. There were different versions of stories about who initiated the contact and how. The one adopted here is from Freiberger and Swaine, Fire in the Valley, 32-34
7. Frank Delaney, “The World’s First Commercially Available PC,” in History of the Microcomputer Revolution (Spokane, WA: KPBX, 1995).
8. Fred Moore, “It’s a Hobby,” Homebrew Computer Club Newsletter, 7 June 1975.
9. Theodor H. Nelson, Computer Lib: You Can and Must Understand Computers Now (South Bend, Ind.: by the Author, 1974), cover.
10. CARL, “The Impossible Dream,” Byte, September 1975.

Introduction (2)

However, it has been debatable about how many of these dreams had come true. Some, if not all, of them seemed to diminish soon. When the famous Apple II hit the market in 1977, it had already become a mandated commodity. Its advertisement warned consumers: “You’ve just run out of excuses for not owning a personal computer.”[11] Instead of creating a new home environment integrated with new ways of computing, the advertisement showed the Apple II as a perfect addition to the young, middle-class household. As the husband leisurely explored why a personal computer was a “must-have,” the wife worked in the kitchen.

Fig. 3. Apple II's First Advertisement in Byte, June 1977. It tells consumers that, "You've just run out of excuses for not owning a personal computer."

While the innovation of personal computers in the 1970s was full of fascinating events and people, historians have not yet settled in interpreting its historical origin. In Computer: A History of the Information Machine, historians Martin Campbell-Kelly and William Aspray pointed out two aspects to consider: “computer liberation” and computer hobbyists.[12] Admitting that it “would, perhaps, be overstating the case to describe computer liberation as a movement,” Campbell-Kelly and Aspray, nonetheless, asserted “there was unquestionably a widely held desire to bring computing to ordinary people.”[13] Campbell-Kelly and Aspray analyzed the historical contexts of computer liberation and and its relationship to the origin of personal computers:

Computer liberation sprang from a general malaise in the under-thirty crowd in the post-Beatles, post-Vietnam War period of the early 1970s. There was still a strong anti-establishment culture that expressed itself through the phenomena of college dropouts and campus riots, communal living, hippie culture, and alternative lifestyles sometimes associated with drugs. Such a movement for liberation would typically want to wrest communications technologies from vested corporate interests.[14]

Further, Campbell-Kelly and Aspray claimed that “the somewhat technologically fixated vision of the computer hobbyists was leavened by . . . the advocates of ‘computer liberation.’” Among these advocators, Campbell-Kelly and Aspray named Ted Nelson, who frequently spoke at computer hobbyist gatherings, as “the most articulate spokesperson.”

If it was overstating to call computer liberation a movement, then it was equally problematic to assume that the innovators of personal computers shared “liberation” as a common goal. The 1970s was, indeed, a period that numerous young, self-taught computer hobbyists pulled together their enthusiasm and talent for computing, and they built from scratch a brand new industry for personal computers. However, Campbell-Kelly and Aspray failed to provide direct evidence to prove that these founding fathers of the personal computer industry were devoted to the idea of computer liberation. Ed Roberts, for instance, had read Ted Nelson’s Computer Lib / Dream Machine, but he developed the Altair 8800 in order to save his business.[15] Moreover, what exactly was the vision of computer liberation that Ted Nelson could have provided the innovators of personal computers, such as Ed Roberts?

Steven Levy claimed a different origin of personal computers in Hackers: Heroes of the Computer Revolution. Levy called the computer hobbyists in the 1970s “hardware hackers,” and thus implied that they were part of the “true hacker” tradition beginning at the Tech Model Railroad Club of the Massachusetts Institute of Technology (MIT) in the 1950s.[16] He used Lee Felsenstein and Bob Albrecht, co-founders of PCC, to illustrate the connection between hackers and the momentum of developing personal computers in the 1970s. However, Levy’s assessment on this connection was also ambiguous. While crediting Felsenstein for “spread[ing] the Hacker Ethic by bringing computers to the people,” Levy also stated that this was a battle that “the MIT hackers had never considered worth fighting.”[17] What, indeed, was the role that hackers played in the innovation of personal computers? More precisely, was it proper to call the innovators of personal computers in the 1970s “hackers,” as Levy did?

As an effort to clarify the questions raised by the studies of Campbell-Kelly and Aspray and Levy, this essay will reinvestigate the mutual relationships among hackers, the visions of computer liberation provided by Ted Nelson, and computer hobbyists. It is also an attempt toward answering what sociologist Manuel Castells has called the unwritten “social history of the values and personal views of some of the innovators of the 1970s Silicon Valley revolution in computer technologies.”[18] In contrast to Paul Freiberger and Michael Swaine’s Fire in the Valley: the Making of the Personal Computer, which focused on the novelty of the technological revolution, its key players and major events, this study emphasized the cultural impacts of hackers and computer hobbyists to the origin of personal computers in the 1970s.[19]

In most cases, this essay will refer to the “minicomputer,” “microcomputer,” “personal computer” and “home computer” that appeared in the 1970s as “personal computer.” There have been attempts to make technical definitions for the minicomputer (in comparison to the big, time-sharing, mainframe computer) by its speed or memory capacity. However, no consensus has been reached for such definition. On the other hand, regarding the social impact of computers, this study focuses on the affordability of a computer to the individual. In the technical aspect, this study stresses the contrast between sharing the time and resources when using a mainframe computer and personally owning a whole yet much less powerful computer. Therefore, the term “personal computer” will be used in this essay unless following the usage in primary sources. The choice of the term “personal computer” also reflects the individualism in the hacker culture and computer liberation, which will be presented in the rest of this essay.

11. "Introducing Apple II." Byte, June 1997, 43.
12. Martin Campbell-Kelly and William Aspray, “The Shaping of the Personal Computer,” in Computer: A History of the Information Machine (New York: Basic Books, 1996), 237-40.
13. Ibid., 238.
14. Ibid.
15. Paul Freiberger and Michael Swaine, Fire in the Valley: The Making of the Personal Computer, Second ed. (New York: McGraw-Hill Book Company, 2000), 442.
16. Steven Levy, Hackers: Heroes of the Computer Revolution (New York: Penguin Books, 1994), 20, 153.
17. Ibid., 158.
18. “There is still to be written a fascinating social history of the values and personal views of some of the innovators of the 1970s Silicon Valley revolution in computer technologies. But a few indications seem to point to the fact that they were intentionally trying to undo the centralizing technologies of the corporate world, both out of conviction and as their market niche.” See Manuel Castells, The Rise of the Network Society, vol. I, The Information Age: Economy, Society and Culture (Massachusetts: Balckwell Publishers, 1999), n. 5, 6.
19. Freiberger and Swaine updated the 1984 edition Fire in the Valley into the 2000 edition with three more chapters, including one entitled as “Fire and Ashes” and Epilogue “After the Revolution.” While Freiberger and Michael Swaine did not change the focuses of Fire in the Valley through these two editions, their updates signaled the end and failure of the computer revolution.

Research Design

This study adopts a different approach and draws conclusion mostly from a set of primary sources—hobby electronics magazines and personal computer magazines—which have been largely overlooked by previous researches. Both Levy’s Hackers and Freiberger and Swaine’s Fire in the Valley relied heavily on interviewing the individuals who led the early development of personal computers. Interviews certainly are important and necessary sources to the historical analysis of personal computers in the 1970s, but they are also limited to each person’s memory and interpretation. In some cases, the information gathered through interviews is contradictory. For example, Roberts as well as Solomon and Salsberg, each reported a different story about who initiated the contact that resulted in the creation of the first personal computer, the Altair 8800.[20] Therefore, new sources are needed to clarify such confusions left by existing researches.

On the other hand, the approach of this research is to analyze hackers and computer hobbyists as communities, while Levy’s and Freiberger and Swaine’s investigations focused on some individuals. Hobby electronics magazines and personal computer magazines, such as Popular Electronics, Radio Electronics, Byte, Dr. Dobb’s Journal, and Creative Computing, from the mid-1970s are suitable for this research because they stimulated the birth of the first generation of personal computers and networked the earliest computer hobbyist community. The articles and advertisements in these magazines represented the readers’ background, technical knowledge, and shopping information in which they were interested. Instead of focusing on technological advancements, this research also pays attention to the way that personal computers were gradually portrayed as a mandated household product in these magazines.

However, this study would not be complete if the analysis were limited to hobby electronics and personal computer magazines. To understand the vision of computer liberation, it is necessary to analyze Ted Nelson’s influential Computer Lib / Dream Machines (1974) and his lesser known The Home Computer Revolution (1977). Finally, in order to sketch out the historical and cultural context of the hacker community, this essay will begin by analyzing the Jargon File and The Hacker’s Dictionary, which have been collected and published by the hacker community since the late 1950s.

20. See Stan Veit, Stan Veit’s History of the Personal Computer (Asheville, North Carolina: WorldComm, 1993), 39, and Theodor H. Nelson, The Home Compute Revolution (South Bend, Ind.: T. Nelson, 1977), 49.

The Computer Priesthood and the Culture of Happy Hacking (1)

Our modern computers are an offspring of wartime military need. In the early twentieth century, “computer” still meant a human profession, not a machine.[21] It meant those people who were hired by the U.S. army’s Ballistic Research Laboratory (BRL) to hand-calculate firing tables for rockets and artillery shells. Because of the wartime male labor shortage during World War II, BRL began to recruit female mathematicians as human computers. On the other hand, BRL supported the University of Pennsylvania where the Electronic Numerical Integrator and Computer (ENIAC) project was created in order to automate ballistics calculation. The project was quite successful.

In the summer of 1945, the first electronic computer was already demonstrating its impressive calculating power. As historian Jennifer Light points out, the ENIAC computer replaced two hundred human computers exactly as planned. Furthermore, this government-sponsored computer industry not only soon forgot its women computers, but also reserved its new positions—programmers and engineers—for men released from military service. Huge machines, super power, and male professionals all became characteristics that people associated with computers in the following decades, and to some extent, even to this day.

Until personal computers came into the world in the mid-1970s, a hierarchical access control system governed how computers interacted with their users. In the three decades following the birth of the ENIAC, a basic computer easily cost several million dollars. Only big companies and well-funded research institutions could afford such computers, and computers were manufactured with the mantra “the stronger, the better.” As a result, no one would risk damaging such valuable property by allowing an inexperienced user access. Indeed, most users of this period never physically touched the computer. For every computer, only a select group of administrators, “priests” in users’ slang, were allowed to physically operate the machines.[22]

This access control system—called the “computer priesthood”—was frustrating to users. With the computer priests mediating between users and the machines, using computers became a ritualistic exchange. No matter how passionate and for what purpose a user requested the computer to perform some calculation, after submitting a program (most often written in the low level machine language on punch cards) to the priests, all one could do was wait. Moreover, the waiting period could range from hours to days. Worse, more often than not, the returned results were not the desired calculation results but a bunch of error messages that hardly explained where the program went wrong. It always required a careful and lengthy check of the program and then its re-submission.

On the other hand, there were some users who enthusiastically fell in love with these mighty machines, regardless of the strict control under the computer priesthood. Such users called themselves “hackers.” Hackers often violated the access regulations, sneaked into machinery rooms, and were never afraid to touch the valuable computers. The waiting period for the computer to return results was unbearable, so they wrote more and kept computers busy with programs that seemed to be wasting the resources of the multi-million dollar machines. Hacker Peter Samson at the Massachusetts Institute of Technology (MIT), for example, wrote one of the earliest programs for playing melodies, with very poor sound quality, on a computer that was designed for mathematical calculation and not for entertainment.[23] This kind of enthusiasm looked insane to outsiders. Furthermore, the computer priesthood did not appreciate the hackers’ obsession with computers.

21. For a more detailed history of the first computer, ENIAC, see Jennifer S. Light, “When Computers Were Women,” Technology and Culture 40, no. 3 (1999).
22. Eric S. Raymond, The New Hacker's Dictionary, 3d ed. (Cambridge, Massachusetts: The MIT Press, 1999), 364.
23. Levy, Hackers, 34.

The Computer Priesthood and the Culture of Happy Hacking (2)

By the early 1960s, the hackers had gradually become a discrete community congregated around local computer centers with its own subculture. In the dictionary that Samson compiled in 1959 according to the subculture of the Tech Model Railroad Club (TMRC) of MIT, which was one of the major origins of the hacker community, “hack” and “hacker” were already defined. “Hack” meant:

1) an article or project without constructive end; 2) work undertaken on bad self-advice; 3) an entropy booster; 4) to produce, or attempt to produce, a hack.[24]

Further, hacker was simply: “one who hacks, or makes them.”[25]While the informal hacker’s dictionary continued growing in the following years, the hacker community continues to honor the self-motivated practices of stretching the machinery capabilities for fun. In 1975, Raphael Finkel at the Stanford Artificial Intelligence Laboratory extended the TMRC dictionary to an online Jargon File to collect more inputs from the hacker community.[26] When Guy Steele transformed the Jargon File into a 136-page paper publication, The Hacker’s Dictionary (THD), in 1983, the image of “hacker” became clearer. A lengthy citation here is necessary to understand how hackers identified themselves:

HACKER noun.

1. A person who enjoys learning the details of computer systems and how to stretch their capabilities—as opposed to most users of computers, who prefer to learn only the minimum amount necessary.

2. One who programs enthusiastically, or who enjoys programming rather than just theorizing about programming.

3. A person capable of appreciating HACK VALUE.

4. A person who is good at programming quickly. (By the way, not everything a hacker produces is a hack.)

5. An expert on a particular program, or one who frequently does work using it or on it. Example: “A SAIL hacker.” (This definition and the preceding ones are correlated, and people who fit them congregate.)

6. An expert of any kind. One might be an astronomy hacker, for example.

7. A malicious or inquisitive meddler who tries to discover information by poking around. For example, a “password hacker” is one who tries, possibly by deceptive or illegal means, to discover other people’s computer passwords. A “network hacker” is one who tries to learn about the computer network (possibly because he wants to improve it or possibly because he wants to interfere—one can tell the difference only by context and tone of voice).


Hackers consider themselves somewhat of an elite, though one to which new members are gladly welcome. It is a meritocracy based on ability. There is a certain self-satisfaction in identifying yourself as a hacker (but if you claim to be and are not, you’re quickly labeled BOGUS).[27]

Notably, only the last definition of “hacker” is close to what the general public thinks a hacker is today. Hackers, for the most part, saw themselves as an elite group of people who were very capable of programming and proud of that capability. On the other hand, nowhere in THD did hackers show any disapproval or need for further clarification to the practice of applying “deceptive or illegal means.” Compared to laws and common ethics, hackers followed their own “hack value,” which was defined as:

HACK VALUE noun. Term used as the reason or motivation for expending effort toward a seemingly useless goal, the point being that the accomplished goal is a hack. For example, the MACLISP language can read and print integers as Roman numerals; the code for this was installed purely for hack value.[28]

It was not until The New Hacker’s Dictionary (TNHD) compiled by Eric S. Raymond in 1999 that hackers finally attempted to clarify their fame.[29] According to TNHD, hackers coined the term “cracker” around 1985 “in defense against journalistic misuse of hacker.”[30] While hackers described themselves as having a “huge open poly-culture,” a cracker was “one who breaks security on a system.” Furthermore, hackers considered crackers’ practice of “gather[ing] in small, tight-knit, very secretive groups” as “a lower form of life.”[31] At the end of TNHD, Raymond even included a sample letter so that the readers could complain to their favorite newspaper when “cracker” should be use in place of “hacker.”[32]

24. Tech Model Railroad Club of MIT, Abridged Dictionary of the TMRC Language, 16 March 2003 <http://tmrc.mit.edu/dictionary.html> (21 March 2003).
25. Ibid.
26. Raymond, The New Hacker's Dictionary, 3d ed., 5.
27. Guy L. Steele, The Hacker's Dictionary: A Guide to the World of Computer Wizards (New York: Harper & Row Publishers, 1983), 79-80.
28. Ibid., 76.
29. The first edition TNHD (1991) corresponded to the 2.9.6. version Jargon File. TNHD 2d ed. (1993) corresponded to the 3.0.0 version, and TNHD 3d ed. (1999) the 4.0.0. version. As of September 2002, Jargon File was at version 4.3.3. Eric S. Raymond, “Jargon File History,” Jargon File 4.3.3 Resources, <http://catb.org/esr/jargon/jarghist.html> (8 May 2003).
30. Raymond, The New Hacker’s Dictionary 3d ed., 130.
31. Ibid.
32. Ibid., 532.

The Computer Priesthood and the Culture of Happy Hacking (3)

However, either it was already too late to make such clarification acceptable to the public, or the distinction between “hacker” and “cracker” was still too vague to outsiders. Hackers felt their behaviors were “some playful cracking” or supported by “practical reasons”—the necessity to “get around some security in order to get some work done”—but a non-technical person had no means to judge how “playful” or “practical” their behaviors were.[33]In TNHD, “hacker ethic” was defined as:

1. The belief that information-sharing is a powerful positive good, and that it is an ethical duty of hackers to share their expertise by writing free software and facilitating access to information and to computing resources wherever possible. 2. The belief that system-cracking for fun and exploration is ethically OK as long as the cracker commits no theft, vandalism, or breach of confidentiality.[34]

Notably, the entry on hacker ethic did not appear before the 1999 edition of TNHD. Moreover, the editor Raymond had to admit that the second definition of hacker ethic was controversial, and that these ethical principles were “widely but by no means universally accepted among hackers.”[35]

Hackers knew that their salvation would never come from the computer priesthood. In the name of serious research and business, the mighty calculating power of computers was used to replace humans, not to serve them. According to the ideology of the computer priesthood, if the computer were a servant, it would exist only for the institution, not for the individual—and certainly not for fun. It was not in the computer’s job description to play music, so none was equipped with speakers! Hence it was more than a technical miracle that Peter Samson made a mute machine sing. With ingenious programming skills, hacker Samson would stretch the capability of computers for entertainment rather than become an obedient programmer under the direction of the computer priesthood.

However, hackers did not bring a reform to the computer priesthood. Hackers resisted letting the computer priesthood confine their individual talents, but they interpreted their actions primarily as enjoyment. Furthermore, there was little evidence that the hacker community had yet developed a more aggressive approach to reform the computer priesthood. After all, the hackers’ passion was for computers, not for human interaction.[36]

The direct connection between the hacker culture and the computer liberation movement in the 1970s also seems vague. For instance, the innovators of personal computers preferred the user friendly programming language BASIC more than the powerful assembly language favored by the hackers.[37] Furthermore, while most hackers subscribed to the belief that “information-sharing is a powerful positive good, and that it is an ethical duty of hackers to share by writing free software and facilitating access to information and to computing resources wherever possible,” such a hacker ethic has not been adopted by the mainstream among practices in the personal computer industry.[38] Later discussions will show that the idea of providing free software was gradually replaced by selling computers with the lure of bonus applications. However, before reaching these subjects, it is necessary to analyze idealist Ted Nelson, who was famous for presenting his vision about what computers should do.

33. Ibid., 130.
34. Ibid., 234.
35. Ibid.
36. See, for example, the “hack mode” entry in Raymond’s The New Hacker’s Dictionary. Described as “one of the most important skills,” a hacker in “hack mode” prioritizes the interaction with computers over that of other people.
37. BASIC is the acronym for Beginner’s All-purpose Symbolic Instruction Code. BASIC is one of the earliest and simplest high level programming languages. The Random House Personal Computer Dictionary (1991), s.v. “BASIC.”
38. Raymond, The New Hacker’s Dictionary, 3d ed., 234.

Nelson’s Dream Machine (1)

Whoever sees the cover of Ted Nelson’s Computer Lib / Dream Machine will immediately be reminded of Jesse Owens’ fist in the black power movement (Fig. 4).

Fig.4. The Cover of Ted Nelson’s Computer Lib / Dream Machine (1974). It is actually two oversized books stuck together back to back, so the flip side of Computer Lib is Dream Machine. This book was so popular that it went through at least three reprints in about a year.

When Nelson self-published Computer Lib in 1974, computers were still expensive, huge, and locked in guarded rooms where only few selected people were privileged enough to touch them. Despite the book’s oversized, unconventional format, Nelson’s visionary slogan: “New Freedoms Through Computer Screens” attracted more than 50,000 readers.[39] It reached “all the right people,” including Ed Roberts and the inventor of the APPLE computers, Steve Wozniak.[40] Indeed, even when a small newsletter, The Amateur Computerist, was published almost fifteen years later in an effort to promote the discussion of automation and industrial unionism, four paragraphs of Nelson’s words were cited as proof of the importance of understanding and using computers.[41]

Nonetheless, exactly what were the computer and new freedom that Nelson dreamt of? Nelson began Computer Lib by coining the term “cybercrud,” which meant “putting things over on people using computers” and functioned to “confuse, intimidate or pressure.”[42] To illustrate what cybercrud was, Nelson provided a letter from a bank that required customers to use computerized deposit slips as proof of how people had to change their way of doing things because of computers.[43] Ironically, while Nelson thought such change was intolerable, today almost no one would feel uncomfortable when using a computerized deposit slip. On one hand, Nelson might think that this was because cybercrud had fooled the public’s consciousness over the years. On the other, this example seemed also fit with Nelson’s statement: “Adaptations should take place on both sides.”[44] Computers were programmed to do banking, and humans made some adjustment in order to communicate with computers through deposit slips. In this example, Nelson did not explain why humans should not make adjustments by filling out new types of deposit slips. Moreover, while warning that “everyone does it,” the computer people, in Nelson’s mind, were guiltier of cybercrud.[45] He said:

Cybercrud is by no means the province of computer people alone. Business manipulators and bureaucrats have quickly learned the tricks. Companies do it to the public. The Press [sic], indeed, contributes . . . . But the computer people are best at it because they have more technicalities to shuffle around magically; they can put anybody down.[46]

Nelson was insightful in pointing out that, “No man has a right to be proud that he is preserving and manipulating the ignorance of others.”[47] Nevertheless, Nelson never clarified who “the computer people” were and precisely how they differed from “the computer fans” that Nelson promoted and identified with.[48] Throughout the book, there were many provocative yet ambivalent statements.

Indeed, Nelson’s contemporaries already knew what was missing in his grand vision. In the popular computer magazine, Byte, a review on Computer Lib in October of 1975 pointed out:

Nelson is a generalist, for the most part, and, like many generalists, his explanations for things are sometimes overtly simplistic. . . . And “practically-minded” engineering types, who are involved in the hard work of actually building interactive computer systems, may snicker at Nelson’s grandiose plans. But ideas like these are desperately needed, and people who use computers would do well to read this book and share its visions. We’re publishing this review in the hope that some of you out there will get the book, seize upon its ideas and turn them into reality (emphasis mine).[49]

Computer Lib was more successful in explaining the essential features of computers to the general public than giving engineers new technical information.[50] Particularly, the technical information contained in Computer Lib was far from enough to put together a personal computer. For those who were interested in this purpose, they need electronics magazines such as Radio Electronics and Computer World. For instance, when explaining the concept of interactive systems, Nelson did not provide more details than “it ‘converses’ with the user.” He only vaguely admitted its theoretical aspects by referring readers to his summary on Artificial Intelligence in Dream Machine—the giant book that was literally at the flip side of Computer Lib.[51] Byte, in contrast, provided readers with the instructions they needed to turn surplus keyboards into input devices for computers; this practically improved the communicative means between humans and computers.[52] It was such hands-on experiments and innovations that more directly brought personal computers into existence than Nelson’s Computer Lib.

39. Nelson, Computer Lib, cover; Christopher Keep, Tim McLaughlin, and Robin Parmar, “Ted Nelson and Xanadu,” The Electronic Labyrinth, November 1995. 29 November 2002.
40. Freiberger and Swaine, Fire in the Valley, 2d ed., 442.
41. “Introduction,” The Amateur Computerist, 11 February 1988.
42. Theodor H. Nelson, Computer Lib: You Can and Must Understand Computer Now (South Bend, Ind.: T. Nelson, 1974), 8.
43. Ibid.
44. Ibid.
45. Ibid.
46. Ibid.
47. Ibid.
48. Ibid., 3.
49. D.H.F., review of Computer Lib / Dream Machines, by Ted Nelson, Byte, October 1975, 82.
50. Introducing the aspects of Computer Lib, Nelson wrote: “The explanations—not yet fully debugged—are intended for anybody.” Nelson, Computer Lib, 5.
51. Ibid., 13.
52. Among the first twelve issues of Byte from September 1975 to August 1976, five of them had technical articles on connecting keyboards to personal computers.

Nelson’s Dream Machine (2)

Nonetheless, one might defend Nelson as a visionary theorist in the same vein that theorists played important roles in the development of modern physics. Further examination, however, reveals that even Nelson’s visions were problematic. First of all, although Nelson criticized IBM’s basic business principle: “once an IBM customer, always an IBM customer,” which he interpreted as designed to control its customer, he did not seem to have escaped from such control. His list of information sources in Computer Lib did not include hobby electronics magazines. Instead, it mostly consisted of references to IBM systems or related technical and mathematical journals.[53]

Secondly, how visionary Nelson was, indeed, debatable. In a lesser known book, The Home Computer Revolution, that Nelson published in 1977, he credited himself for having point out repeatedly since the mid 1960s that the future market for computers was in the home.[54] However, Nelson spent only one page to introduce minicomputers in Computer Lib, and his endorsement was limited to suggest: “For several families with children to pool together and buy one for the kids makes a lot of sense.”[55] Ironically, the earliest personal computers were not aimed at children’s educational needs, but were marketed more like hobbyists’ toys. Lastly, the innovation of personal computers might have been completely outside the scope of Nelson’s expectations. He constantly used “accidental” to describe the birth of Roberts’ Altair computer. In his descriptions, the amateur computer club was a “strange phenomenon,” and the hobbyists who tried to figure out how to build their own computers were “a peculiar breed.”[56]

An analysis on Nelson’s emphasis on computer graphics (CG) in Computer Lib will summarize the remote possibility that his vision could have directly lead to the innovation of personal computers in the 1970s. In his Dream Machine, Nelson devoted one-fifth of the contents to discuss CG, then the most advanced and fancy technology that only a special designed mainframe computer could perform. Apparently, CG was Nelson’s favor. However, the development of CG for personal computers turned out to disagree with some of Nelson’s advocacies. Nelson downplayed the importance of hardware. Yet CG did not become a standard feature of personal computers until the mid-1990, not because its theory or software was not developed, but because the necessary CG hardware was too expensive for the general public. Therefore, CG had long been a technology that only rich users could enjoy. Nelson’s advocacies were almost never related to the financial affordability. Instead, it was “the computer people” whom Nelson blamed for manipulating technology that had worked diligently for decades to finally bring CG to the common personal computer users.

The sadness of Nelson’s story was not that he failed to propose a workable paradigm for his contemporary computer hobbyists. Instead, it was in the fact that there was no one more visionary than Nelson. The editor of Byte commented in 1975 that Nelson’s ideas were overly simplistic, but none in the following decades came foreword with a better vision than Nelson. Nelson once said: “I thought there would be a real computer revolution; I see complete betrayal.”[57] If Computer Lib represented the vision of the computer revolution in the mid 1970s, then it was too vague and arbitrary to be put into reality. In this vein, Nelson was a lonely revolutionist, who was not betrayed but lacked followers.

53. Nelson, Computer Lib, 6-7.
54. Nelson, The Home Computer Revolution, 44
55. Nelson, Computer Lib, 36.
56. Nelson, The Home Computer Revolution, 49-51.
57. Freiberger and Swaine, Fire in the Valley, 2d ed., 441.

Electronics Hobbyists (1)

While Nelson blamed the shortsighted industry giant IBM for never attempting to “develop personal luxury computer systems for the very rich,” some people took this matter into their own hands.[58] They were not rich families that pooled money together to buy computers for kids, as Nelson had expected, but a “peculiar breed” of engineers whose hobby was playing with any available and affordable electronic hardware.[59] Without doubt, many of these hobbyists must have read Nelson’s Computer Lib and would have been influenced by his vision. However, what connected the electronics hobbyist community was electronics magazines such as Popular Electronics, Radio Electronics, and Electronics World, which Nelson did not mention in his recommended resource list.

Fig. 5. A typical article from Radio Electronics, March 1974. Its logic and circuit diagrams occupied more space then the textual description.

Such hobby electronics magazines, indeed, have their peculiar tradition. Radio Electronics and Electronics World, for example, were first published in the 1950s. Hobby electronics magazines were highly hardware-oriented. Diagrams of electronic logic accompanied most of their articles. Moreover, these magazines appreciated innovations and experiments. Fig. 5 above is a typical article that appeared in Radio Electronics in the 1970s. Besides the huge diagrams that occupied more space than its textual description, the editor of Radio Electronics inserted a note to readers:

This is not a construction article! We have not seen an assembled version of the Electronic Casino. However, this story does contain enough information to enable a reader who expects to do a bit of experimenting to build the unit. If you do build your own version of the Electronic Casino, we’d appreciate receiving a glossy photo of the assembled unit and will publish it in our Letters column. —Editor[60]

Hobby electronics magazines encouraged readers to share their experiences. They were not only one-directional information distributors, but also open discussion forums for hobbyists. Hobbyists looked for interesting electronics projects in these magazines, and they worked together to produce more projects. When a hobbyist needed more parts or instruments for expanding a particular project, he or she could easily collect them from advertisements in electronics magazines.

Indeed, the minicomputers that appeared in the July 1974 issue of Radio Electronics and the Altair 8800 featured in the January 1975 issue of Popular Electronics were just some of the diverse topics that electronics magazines covered. A quick examination of the magazines from 1973 to 1975 showed that although a large proportion of the articles were related to Hi-Fi sound systems or radios—then the most popular electronics—their topics actually ranged from automobile tape players to home electronic security alarms and to color televisions. Probably the most interesting was the cover story of the January 1975 issue of Radio Electronics: “Build a Brainwave Monitor and Turn-Up Your Mind,” which appeared exactly when the first affordable personal computer was shown on the cover of Popular Electronics.

Assembling one’s own computer did not seem an unusual practice to hobbyists. Unlike Computer Lib, which gave a survey about how to buy computers, the articles in hobby electronics magazines discussed how to build appliances. Radio Electronics, for instance, showed the picture of a Brainwave Monitor as a hand-assembled circuit board directly attached to a person’s head by some wires. Similar to the Altar 8800 and many of the earliest personal computers, the Brainwave Monitor did not have an attractive appearance. It was not enclosed in a case and literally was a board with a number of chips and wires. In fact, this is one of the characteristics that distinguish an electronics hobbyist from a general consumer. Hobbyists enjoy the assembly process and innovation. Their productions are always works in progress, because hobbyists always want to add new ideas and additional parts to their projects. Therefore, there was no need to put a hobbyist’s on-going production into an inaccessible box. Consumers, however, want workable products that are self-contained. When there is a need to perform some repair or to add new parts, many of them will choose an official repair services rather than doing the work themselves.

58. Nelson, The Home Computer Revolution, 44.
59. Ibid., 51.
60. Waller M. Scott, “Electronic Casino,” Radio Electronics, March 1974.

Electronics Hobbyists (2)

Besides advertisements that offered necessary materials to hobbyists, electronics magazines had another important characteristic—they were full of advertisements for education and career opportunities (Fig. 6).

Fig. 6. Home-study courses advertised
in Electronics World, June, 1974.

These advertisements often used descriptions such as “college level course quality” and “a career in engineering.” Apparently, the advertisers were assuming their readers were different from those of the engineering journals, who probably already had more than a college degree and held prominent academic or industrial jobs.

To some extent, this reflected the difference between hackers and hobbyists. On the one hand, hobbyists and hackers were similar because both were fond of machinery. The hobbyists’ enthusiasm for electronics projects certainly qualified them as hackers. This was also the reason why Steven Levy treated hobbyists as part of the hacker tradition in his Hackers: Heroes of the Computer Revolution. On the other, the hobbyists who developed the earliest personal computers were not in the same elite status as hackers, who were largely affiliated with the research institutions at universities. Despite the control of the computer priesthood, hackers already had access to computers. Most hobbyists, however, had to build themselves computers because they did not necessarily have the formal qualifications that the computer priesthood sought.

The story of Steve Wozniak further illustrates the difference between a hobbyist and a hacker. Wozniak was well known as “Woz” for his prodigiously engineering talent in personal computers.[61] However, Wozniak did not have a college degree when he co-founded Apple Computer Co. with Steve Jobs in 1976 in Jobs' family garage.[62] At that time, Wozniak was only a junior technician at Hewlett-Packard.[63] There was no computer that Wozniak was allowed to access at his workplace, and Hewlett-Packard had denied his request for a transfer to a computer-related division. If Wozniak was serious about his hobby, he had to begin by building a computer for himself. Fortunately, Wozniak was indeed serious. Moreover, because the Altair 8800 was still too expensive for Wozniak, he designed a new personal computer, called the Apple I, based on a cheaper processor—the Mostek 6502 at $20 apiece.[64] In two years, Steve Jobs had successfully transformed this hobbyist’s project into a popular consumer product, the Apple II.

Although nobody will deny that Wozniak is one of the best personal computer hackers, the classic hacker community was suspicious about personal computers, their hobbyists and users. When Steele edited THD in 1983, he was concerned about the threat of personal computers to the hacker culture. He predicted:

hackerdom might be dying—killed off, ironically, by the spread of knowledge about computers. As programming education became more formalized, as the personal computer atomized hacker communities previously knitted together by timesharing, and as the lure of big money in industry siphoned off some of the best and brightest, it seemed as though hackerdom’s unique values might be lost.[65]

Steele’s negative evaluation of personal computers was not a singular event among classic hackers. When Raymond tried to restore the hackers’ reputation in the 1990s, he not only emphasized the difference between hackers and the users of personal computers, but also implied that crackers originated from personal computer users. As Raymond wrote in the 1993 third edition of TNHD:

From the late 1980s onward, a flourishing culture of local, MS-DOS-based bulletin boards has been developing separately from Internet hackerdom. The BBS culture has, as its seamy underside, a stratum of pirate boards in habited by crackers, phone phreaks, warez d00dz [sic]. These people (mostly teenagers running PC-clones from their bedrooms) have developed their own characteristic jargon, heavily influenced by skateboard lingo and underground-rock slang.

Though crackers often call themselves ‘hackers’, they aren’t (they typically have neither significant programming ability, nor Internet expertise, nor experience with UNIX or other true multi-user systems). Their vocabulary has little overlap with hackerdom’s.[66]

Moreover, while Steele’s prediction “didn’t survive an editor’s objections” and was not published until Raymond’s TNHD in 1991, it is noteworthy that hackers did not have an entry for “priesthood” in THD either.[67] According to TNHD, “priesthood” could be traced back to the TMRC at MIT in the 1950s. It was not a phrase limited to the TMRC or MIT hacker community because other writers such as Nelson also used this term in their descriptions.[68] Why, then, was “priesthood” not included in THD or Jargon Files until the 1990s? Steele and other editors said at the very beginning of THD: “This, we warn you, is supposed to be a fun book [sic]."[69] Hackers, and the editors of THD included, probably were so indulged in the image of hackers happily working in a computer laboratory that they half-consciously ignored the restrictions that the computer priesthood had placed upon them. In this vein, the classic hackers portrayed themselves as an elite group, which happily worked with the mighty time-sharing computers, in contrast to the technically insignificant and sometimes evil-intentioned owners of personal computers.

The fact that classic hackers did not view personal computers as a challenge to the computer priesthood but to the hacker culture shows that the tradition of electronics hobbyists, instead of hackers, was more important to the innovation of personal computers in the 1970s. Surely the hackers and hobbyists communities had some overlaps. However, most of the important personal computer innovators—Steve Woz, Steve Jobs, Ed Roberts, etc.—did not have connection to the university-based hacker community. Furthermore, hackers suspected personal computer users for damaging their reputation and culture. Therefore, electronics hobbyists should be distinguished from hackers when analyzing the origin of personal computers in the mid-1970s.

61. Al Luckow, “Short Bio for Steve Wozniak,” Personal website for Steve "The Woz" Wozniak, 4 January 2000, <http://www.woz.org/wozscape/wozbio.html> (April 28, 2003).
62. Ibid.
63. Stephen Segaller, Nerds 2.0.1: A Brief History of the Internet (New York: TV Books, 1999), 151.
64. Levy, Hackers, 251.
65. Guy L. Steele, “Confessions of a Happy Hacker,” in The New Hacker's Dictionary, 3d ed., Eric S. Raymond (Cambridge, Massachusetts: The MIT Press, 1999), xiv.
66. According to Raymond’s explanation of the cracker culture, “phreak” is an intended misspelling of “freak” and crackers referred to themselves as “warez d00dz.” Raymond, The New Hacker’s Dictionary, 24, 478.
67. Steele, The Hacker's Dictionary, xiv.
68. Nelson, Computer Lib, 2.
69. Steele, The Hacker’s Dictionary, 7.

From a Hobby to an Industry

Personal computer magazines soon flourished after the arrival of the Altair 8800 in January 1975. The old hobby electronics magazines, which occasionally offered special topics on computers, no longer could satisfy the fast growing population of personal computer hobbyists.[70] Byte, for example, published its first issue in September 1975. Together with Dr. Dobb’s Journal published by People’s Computer Company, Byte as well as some other earliest personal computer magazines remains popular to this day.

Beside their focus was solely on personal computers, personal computer magazines inherited most of the characteristics from hobby electronics magazines. First of all, “hands-on” was still the key word. For example, among the eighteen articles on video displays that Byte published in its first year, ten discussed how to construct graphics interfaces or monitors; even the two product reviews were on graphics processors and interface kits. Unlike later consumers who could simply buy a ready-made interface card or monitor, earliest owners of personal computers had to build most parts by themselves.

Therefore, advertisements played the same or even more important roles in personal computer magazines than in hobby electronics magazines. Readers could order chips and boards from the companies advertising in the magazines to improve their computers. Moreover, they got the information about the newest models of personal computers by reading advertisements. Besides the Altair 8800 from MITS, every issue of Byte had advertisements for personal computers from other companies—the SCELBI-8B, SPHERE 1 System, IMSAI VDP 80, etc. These advertisements always contained detailed, and sometimes over-promised, feature lists for their computers. While very few readers could offer to buy several personal computers in a short period of time, these advertisements at least kept them updated with related technology and products.

Further analysis on personal computer magazines shows how fast the industry of personal computers grew. When the photo of Apple I first appeared in the April 1976 issue of Byte, it looked as unattractive as most other personal computers—a single board without even a power supply or a case (Fig. 7).
Fig. 7. Photo from Apple I’s First Advertisement in Byte, April 1976
Compared with the four-page, color advertisement of Apple II that appeared just fourteen months later (Fig. 3), Apple Computer and the whole industry certainly had accomplished a lot. In fact, Apple II was a success because it strove to include most features that a personal computer should have. Enclosed by its pretty plastic box were features like keyboard, graphics interface, and tape storage interface, and it came with the basic yet necessary software support. While other personal computers might have come with one or two of these features, Apple II was the first personal computer to include all of them in a box for $1,298 (roughly equivalent to $3,863 in 2002 dollars).[71]

Moreover, Apple Computer transformed the personal computer from a hobbyist project to a consumer product. When many companies still charged extra fees for assembling, Apple I and Apple II were sold only assembled. The concept of building a computer was replaced by using one, and the advertisement of Apple II proudly announced: “Only Apple II makes it that easy. It’s a complete, ready to use computer, not a kit.”[72] While the flyer of Apple I still claimed, “it opens many new possibilities for users and systems manufacturers,” the advertisement for Apple II warned: “You’ve just run out of excuses for not owning a personal computer.”[73]

70.Popular Electronics, for example, had only two cover stories on personal computers in 1975.
71. “Introducing Apple II,” Byte, June 1977, 45.
72. Ibid., 43.
73. Steven Weyhrich, “Apple-I Advertisement,” Apple II Historical Museum, 2003 <http://apple2history.org/museum/ads/a1ad1.html> (28 April 2003); “Introducing Apple II,” Byte, June 1977, 43.


An Unfinished Revolution

The computer revolution happened in the mid-1970s, as proclaimed in the Homebrew Computer Club Newsletter, originated from “a hobby for fun.”[74] These computer hobbyists were certainly heroes. However, this study showed that computer hobbyists were different from hackers, who worried that personal computers had become a threat to their culture. While most historians would agree that the direction for developing computer technology had changed dramatically since the innovation of the Altair 8800 in 1975, it is still uncertain who should be credited for this change. This study suggests computer hobbyists as a more possible candidate than hackers.

The whole story of personal computers is more complicates than has been presented in this essay, and the story itself certainly has not ended yet. In 1980, IBM finally decided to enter the market of personal computers, and it acted fast.[75] In August 1981, the IBM Personal Computer was already in retail stores.[76] By 1984, IBM sold two million computers and the IBM Personal Computers had become an industry standard.[77] While Apple Computer and IBM continuously fought for their market shares in the following years, both companies eventually lost to Microsoft, which was a company devoted solely to software development. Moreover, if the personal computer has “atomized” its users—as Steels had once complained—then the rise of the Internet in the 1990s was again redefining the computers.[78] Will the combination of the Internet and personal computers finally achieve the hackers’ belief in information-sharing?[79] Nobody has an answer to this question, but surely many will come forward and attempt to finish this revolution.

74. Fred Moore,. “It’s A Hobby,” Homebrew Computer Club Newsletter (Menlo Park, CA). 7 June 1975.
75. Campbell and Aspray, “The Shaping of the Personal Computer,” 253.
76. Ibid., 256-57.
77. Segaller, Nerds 2.0.1, 183.
78. Steele, “Confessions of a Happy Hacker,” xiv.
79. Raymond, The New Hacker’s Dictionary 3d ed., 234.


Primary Sources:
Byte, September, 1975 – December, 1977.
Creative Computing, December 1974 – December 1976.
Dr. Dobb’s Journal, January, 1976 – December 1976.
Electronics World, January, 1974 – December, 1975.
Popular Electronics, January, 1974 – December, 1976.
Radio Electronics, January, 1974 – December, 1975.
The Amateur Computerist, 11 February 1988.
Nelson, Theodor H. Computer Lib: You Can and Must Understand Computers Now. South Bend, Ind.: by the author, 1974.
________. The Home Computer Revolution. South Bend, Ind.: by the author, 1977.

Secondary Sources:
Bard, Doug. The People’s Computer Company Alumni Pages. 15 May 2001 (29 November 2002).

Campbell-Kelly, Martin, and William Aspray. “The Shaping of the Personal Computer.” In Computer: A History of the Information Machine, 233-58. New York: Basic Books, 1996.

Castells, Manuel. The Rise of the Network Society. Vol. I, The Information Age: Economy, Society and Culture. Massachusetts: Blackwell Publishers, 1999.

Damer, Bruce. The DigiBarn Computer Museum. <http://www.digibarn.com> (13 November 2002).

Delaney, Frank. “The World’s First Commercially Available PC.” In History of the Microcomputer Revolution. Spokane, WA:KPBX, 1995.

Espinosa, Chris. “It Wasn't Supposed to Be Like This: The People Lost. The Priesthood Won.” MacTech 11, no. 1 (1995).

Freiberger, Paul, and Michael Swaine. Fire in the Valley: The Making of the Personal Computer. Berkeley, California: Osborne/McGraw-Hill, 1984.

________. Fire in the Valley: The Making of the Personal Computer. Second ed. New York: McGraw-Hill Book Company, 2000.

Himanen, Pekka. The Hacker Ethic: A Radical Approach to the Philosophy of Business. New York: Random House, 2001.

Keep, Christopher, Tim McLaughlin, and Robin Parmar. “Ted Nelson and Xanadu.” The Electronic Labyrinth. November 1995. <http://www.iath.virginia.edu/elab/
> (29 November 2002).

Levy, Steven. Hackers: Heroes of the Computer Revolution. New York: Penguin Books, 1994.

Light, Jennifer S. “When Computers Were Women.” Technology and Culture 40, no. 3 (1999): 455-83.

Luckow, Al. Personal website for Steve "the Woz" Wozniak. <http://www.woz.org> (12 November 2002).

Margolis, Philip E. The Random House Personal Computer Dictionary. New York: Random House, 1991.

Raymond, Eric S. The New Hacker's Dictionary. Cambridge, Massachusetts: The MIT Press, 1991.

________. The New Hacker's Dictionary. 3d ed. Cambridge, Massachusetts: The MIT Press, 1999.

Segaller, Stephen. Nerds 2.0.1: A Brief History of the Internet. New York: TV Books, 1999.

Steele, Guy. “Confessions of a Happy Hacker.” In The New Hacker's Dictionary, edited by Eric S. Raymond, ix-xiv. Cambridge, Massachusetts: The MIT Press, 1999.

________. The Hacker’s Dictionary. New York: Harper Collins Publishers, 1983.

Veit, Stan. Stan Veit's History of the Personal Computer. Asheville, North Carolina: WorldComm, 1993.

Weyhrich, Steven. Apple II History. <http://apple2history.org/> (25 April 2003).

Williams, Gregg, and Mark Welch. “A Microcomputing Timeline.” Byte, September 1985, 198-207.