The long road: from ENIAC to iPad

Allikas: KakuWiki
Jump to navigationJump to search


What was in the beginning...

... is still under discussion (both in IT and otherwise).

But it is likely that humans started to compute soon after the first days. Besides fingers, sticks and stones, one of the first computing devices was probably the abacus that came into use as early as about 2700-3000BC (different sources offer different dates, e.g. Ifrah[1] suggests 2700BC). Another device that could be considered a sort of computer was the weighing scale used to compare the weight of an object with another. A very interesting find has been the Antikythera mechanism which was recovered only in 1900AD but is thought to be an astronomical computer dating back to 100BC [2].

Some sources[3] suggest that Leonardo da Vinci designed also a mechanical calculator (around 1492-93). The calculating clock by German professor of Hebrew and astronomy Wilhelm Schickard allowed addition and subtraction of up to six-digit numbers - the blueprints of the machine were rediscovered only in the 19th century [4]. On the other hand, the device built by Blaise Pascal - known as the Arithmetic Machine, Pascal's Calculator and Pascaline - has been known for a long time and considered by many the forefather of today's computers. A number of sources suggest the initial motive for building the device to help his father Étienne who in 1639 was appointed the King's commissioner of taxes, thus having to perform a lot of complicated calculations[5].

Older people may still recall a calculating device called the slide rule which was once taught at schools (in the former USSR, it went on up to the 80s - partially due to the electronic calculators being largely unavailable) and is sometimes still seen in the hands of 'old school' engineers. It was invented in 1632 in Oxford by a mathematician and Anglican minister[6] William Oughtred who built his invention on the logarithmic scale by another Englishman, Edmund Gunter. The cursor or runner (the sliding window with a marker) was added by John Robertson in 1775[7] (other sources point to French artillery lieutenant Amédée Mannheim, who is said to give the rule its present form in 1859).

Modern computers use binary number system. In the modern context, it was first formalized by Gottfried Wilhelm Leibniz (who also built his version of calculator called the Stepped Reckoner in 1673), the traces of binary system however lead to a much more ancient time (some sources point to ancient India and a mathematician named Pingala living in the 2nd or 4th century before Christ). An early example of a programmable device can be found in the Jacquard loom by a French weaver and merchant Joseph Marie Jacquard. The loom used punched cards to set the pattern for the textile.

In 1822, English professor Charles Babbage designs the Difference Engine, followed by the larger and more complex Analytical Engine in 1830. Although both machines were not finished, they are considered an important step in the history of computing (some of them have been built lately to prove the validity of their concepts[8]. The Difference Engine was powered by cranking a handle[9], the Analytical Engine was to be steam-powered.

Quite exceptionally for the period, Babbage was assisted by a young lady named Augusta Ada Byron, daughter of the famous English poet and later Countess of Lovelace. Babbage considered her one of the few people understanding his ideas, calling him "the Enchantress of Numbers"[10]. She prepared a set of instructions (algorithm) for the to-be-built Analytical Engine that has been validated by later researchers as correct. Thus she is often considered the first programmer in the world - among other things, the new programming language designed by the US Department of Defense in 1979 was named Ada after her.

In 1837, Samuel Morse invents the Morse code, the first globally used method for data transmission (telegraph in its heyday was perhaps the most extensive unified information system before Internet). Likewise, the punched telegraph tape invented in 1857 by Charles Wheatstone was the first widely used medium for data recording, becoming the forerunner of floppies, CD/DVD records and memory sticks.


The first modern computer

... is a hotly debated issue again. Various suggestions have been made, but four of them seem to be the most common:

  1. ENIAC (Electronic Numerical Integrator And Computer) was launched in 1943 at the University of Pennsylvania by a team led by John W. Mauchly and J. Presper Eckert[11].
  2. ABC (Atanasoff-Berry Computer) was completed a year earlier, in 1942, at the Iowa State College by John Vincent Atanasoff and Clifford Berry[12]. It is interesting to note that the bitter rivalry between the two machines and their builders spanned over several decades - while ENIAC was initially considered first, the 1973 court case decided in favour of Atanasoff and Berry[13]. On the other hand, several other factors show ENIAC as a more complete machine that also found more use.
  3. The Colossus series were built by British cryptanalysts during the WWII to assist in breaking German codes. Yet, as the ABC, the were not 'complete' computers and were dedicated to a single type of tasks[14].
  4. Z3 and other machines built by Konrad Zuse in Germany. The original Z3 was destroyed in the war and the work of Zuse fell into obscurity. Yet his machines could be perhaps considered the closest to the modern ones[15]. It used the binary system (contrary to the ENIAC's decimal) and Zuse's programming language called Plankalkül is said to contain most of the features of ALGOL, the language from the 50s usually considered the first[16]. On the other hand, Z3 was an electro-mechanical, not an electronic device. Thus, the whole matter is still largely undecided.


The Stone Age

In 1947, one of the best-known anecdotal stories in computing took place - a computer operator (most sources suggest that it was 'Grandma COBOL' or Grace Murray Hopper) searched for a reason of the computer not working, and finding a dead moth between two relay points, taped it to the log book and added the notice "The first actual case of a bug being found". This is considered the birth of the computing terms of "bug" (error), "debug" (finding and fixing errors) and "debugger" (error finding/fixing software[17].

In 1950, Alan Turing formulated the Turing test to determine if a machine is capable of intelligent behaviour[18]. Simply put: the machine is considered intelligent if a human interacting with it cannot determine if he/she is interacting with another human or a machine. During the same year, the first computer named MESM is also built in the Soviet Union. While the Communist countries had a good share of talented mathematicians to provide a theoretical base for technology, they fell seriously behind in the realm of computing - two main reasons being the closedness as well as the overall ignorance (including labelling of many kinds of actual research like psychology and cybernetics 'Western pseudoscience'[19]) and ineffectiveness of the regime[20].

During the fifties, two important technologies contributed towards the miniaturization of computing technology - in 1954, Texas Instruments started to mass-produce [1] (which were actually invented already in 1934) and in 1958, the same company introduces the integrated circuit.

Another noteworthy person who was clearly ahead of his time in the 60s was Douglas Engelbart - the computer mouse was first patented by him in 1963[21] (but became widely used only in the 80s). He went on to develop hypertext (the most common example of the principle nowadays being the Web with its linked pages) and by 1968, an early graphical user interface (which is today used by all widely used computer systems, examples being MS Windows, Apple OS X as well as several desktop systems of variants of Unix and Linux). His 1968 demonstration of then-future computer technologies was later nicknamed The Mother of All Demos[22].

In 1966, IBM develops the first magnetic disk systems. At first, the "hard disks" of the day were huge, cupboard-like devices which gave rise to various 'urban legends' - e.g. the one about walking disk drives[23]. However, some years later in 1971, the company already produced the first generation of the floppy disks, the 8-inch diskette[24].

The year of 1969 has several important landmarks in the history of IT. It can be considered the birth year of Internet, as the first packet switching network (the communication is done by small chunks of information called packages, which travel independently over the network; the principle is a basic one in today's Internet as well) connects four universities in the US[25] - at first, the network becomes known as ARPANET. The AT&T develops the first version of Unix, the first computer operating system being widely portable[26] and eventually becoming a parent for today's two well-known systems in Apple OS X and the Linux family.


The Bronze Age

In 1971 Ray Tomlinson, an engineer at MIT, managed to send a message from one computer to another[27] - his system gets adopted by the ARPANET the next year, becoming what we know today as e-mail.

In 1972, Intel released the first 8-bit microprocessor - with its frequency of 200kHz, it looks antique in comparison with todays 2GHz+ models, yet it was an important step towards personal computers. In the same year, two young men named William Henry Gates III and Paul Allen, create their first company to sell a simple system for traffic density analysis - both the device and the company were called Traf-O-Data. On another front, the newly formed company called Atari releases its first commercial video game titled Pong - while not the first computer game in history, Pong is definitely a forefather of game consoles like Nintendo, Playstation or X-Box. And finally, diskettes started to shrink - the new ones went from 8 inches to mere [2].

Another anecdotal story recalls the first use of real-time text chat over the network - and as so characteristic to the Internet, it was a bit knocked-off by nature: someone at Stanford acted as a mental patient, asking advice from a 'psychiatrist' sitting in Massachusetts[28]...

The landmarks of 1973 include the CP/M, an operating system by Gary Kildall which among other machines was also popular on various computers built in the Eastern Bloc of the day (e.g. the Juku in Estonia); the specification of Ethernet by Bob Metcalfe which is still today the main standard for local computer networks[29]; FTP is devised to move files over the network; IBM releases its first series of hard disks codenamed Winchester - the name would become the generic term for hard disks for some time.

1975 is the birth year of a big player in the world of software. Two guys from Traf-O-Data wrpte their version of the well-known BASIC programming language and renamed their company Microsoft (at first, in the form of 'Micro-Soft'). They also created a substantial controversy by starting to ask money for every copy of their software, a concept totally alien back then. Bill's attempt to convince users that the new model works well was not considered very successful[30]. Two signs from that year indicated the growing mainstreaming of computers - a retail store chain specializing on computers ('Computer Store') was founded, just as the first specialized magazine titled "Byte". ARPANET opens the first mailing lists[31].

Apple was founded just a year later in 1976 by Steve Jobs and Steve Wozniak. While Gates and Allen started with and stayed mostly on software, Apple started out as a hardware company selling the do-it-yourself type Apple I.

It perhaps noteworthy that even if Microsoft Excel is nearly synonymous with spreadsheet software for many people, the first spreadsheet clearly predates Microsoft system - the first was VisiCalc, released in 1979. The same year gave us also Usenet newsgroups[32] and first MUDs[33].

While Microsoft definitely has many friends, the controversies surrounding the company started early on as well. There are several different story versions about the 1980-81 birth of MS DOS, the first best-selling software by Microsoft - the official version by the company[34] recalls buying the system from the Seattle Computer Products, some more critical voices suggest far less favourable scenarios[35]. On the hardware front, Sony released the highly successful [3.5-inch diskette], and in co-operation with Philips, develops the first version of CD audio standard.

Microsoft's historical dominance started with their luck (or business skill, depending on the view) to strike a deal with IBM to supply operating system for their new |http://en.wikipedia.org/wiki/Ibm_5150 Personal Computer Model 5150], which went on to be the first of the whole generation of personal computers. Among three candidates, IBM chose MS-DOS and the huge sales of the computer translated into a huge success for the operating system vendor.

The Iron Age

1982 was the year of rapid spread for the IBM's PC - an important reason being the emergence of the PC compatibles or "PC clones". Due to some technical factors, IBM could not withhold others from copying the design - the fact that was initially considered a curse but came out a blessing. At the time of its birth, IBM PC was one of the many kinds of personal computers available, by 1986 the market share of PC compatibles had exceeded 50%[36]. A number of technically more advanced designed were forced out of the market. This could be seen an important lesson about the power of open standards. The same year, Mouse Systems introduced their mouse for PCs, yet it remained a little more than curiosity for several years (largely up to the emergence of Microsoft Windows 3.0 in 1990; in contrast, Apple made mouse an integral part of their systems remarkably earlier). ARPANET extends to the United Kingdom and Norway, becoming Internet. Scott Fahlman proposes using emoticons (also known as smileys) to denote emotions in online texts[37] (there are also differing views on the origin).

In 1983, IBM produced a next model of PCs, the 5160 or PC XT, which was the first model with a (typically 10MB) hard disk. Apple counters with Lisa and IIe - also, one of their trademark models, the Macintosh (giving its name to all later Macs) was released about then (different sources mention either 1983 or 1984). Microsoft announced the initial version of a new environment named Windows - yet it was released only in 1985 and became practically usable (more or less so) with the version 3.0 in 1990.

It is noteworthy that while there was no Windows, there were already several providers of what we nowadays know as office software - e.g. Lotus 1-2-3, WordPerfect, Multi-Tool Word and others. Yet in the realm of word processing, perhaps the most successful software product of the early 80s was WordStar - it was originally designed for CP/M, but due to good portability took soon over the PC market as well[38].

In general it was the time of entrenchment of the proprietary, commercial and closed software model. Yet there was an 'old school hacker' named Richard Stallman who decided to rebel against it - at the end of 1983, he announced a plan to re-write the widely used Unix operating system and give it freely away to anyone interested[39]. While many people shrugged on the idea, he was determined and launched the GNU project which became the foundation of the Free Software movement. This topic will be covered more thoroughly in the next lectures.

Finally, Fidonet was also born that year - the dial-in (BBS) based network which was especially popular in places where local phone calls were inexpensive or free and vice versa, computer access was restricted (including the former Eastern Bloc). Only when the Internet became the household word at the end of the century, did it back down but is maintained by enthusiasts till today.

1984 was the beginning of mass-produced CD-ROMs and IBM released PC AT which was a substantial improvement over the XT (from the software point of view, the IBM compatible computers have not changed much since then - still, the hardware side as well as the overall performance have changed dramatically). Massachusetts Institute of Technology releases the first version of X Window System - interestingly, the Unix standard of graphical user interface predates Microsoft Windows by several years. In Moscow, Alexey Pajitnov wrote one of the most popular computer games - Tetris. It was followed by a multitude of both legal and not-so-legal copies, one of them which created a real boom among Estonian computer users at the end of the 80s (Tallinn University of Technology even organised a championship tournament!) was aptly named 'Totrus' (Estonian for 'folly', 'stupidity', also 'rubbish').

By the mid-80s, Internet had matured to be a widespread, yet mostly academic and non-profit (commercial activities like advertisement were prohibited) entity, with e-mail, Telnet, FTP and Usenet as its main services.

In 1987, Microsoft and IBM teamed up and announced a new operating system named OS/2. The system can be considered a classic example of a superior product falling victim to the market manipulations - after some years, Microsoft backed out with most of the know-how obtained going into their new Windows. While IBM kept OS/2, it was thoroughly hampered by the rights on some parts which belonged to Microsoft, and was never able to really take off.

In 1989, CERN in Switzerland is connected to the Internet. A staff member named Tim Berners-Lee starts to work on an idea of scientific documents linked together as hypertext - today we know it as the Web[40].

1990 is the release year of the first version of MS Windows that was stable enough for wider public - Windows 3.0. Still, its moderate success was surpassed by far by its very popular successor, 3.1. The University of California, Berkeley introduced the BSD Unix system family. Since then, they have been a rather significant niche systems since (especially in business server systems, due to a liberal licence; OpenBSD is also considered one of the most secure systems in its default configuration), but are also notable for forming the base of Apple OS X (Apple built a commercial "upper layer" on Darwin, a variant of BSD).

The Internet Age

1991 was another landmark year. Tim Berners-Lee published his method of hypertext (notably under public domain - had he chosen otherwise, saying that the world would have been different is not an exaggeration). In the United States, the National Science Foundation lifts the ban on the commercial use of Internet[41] - it makes possible a lot of new services, but also opens the door to spam and cybercrime. A student of the University of Helsinki in Finland named Linus Torvalds announces his "new Unix-like operating system" hobby project[42], later known as Linux.

The next year, Microsoft releases one of their most successful systems which makes Bill Gates the richest person in the US: Windows 3.1, followed by the success of the enterprise-oriented NT series. In Internet, the Web technology started its explosive growth. In 1994, Mark Andreessen and Jim Clark founded Netscape and created their browser of the same name, a successor to the first widely used web browser Mosaic.

For awhile, Microsoft downplayed the role of the Internet, preferring to focus on their own proprietary Microsoft Network. By 1995, they had learned of their mistake and decided to catch up[43]. At first trying unsuccessfully to convince Netscape to divide the market[44], they obtained a Mosaic-derived browser from Spyglass and developed it into the [Internet Explorer http://en.wikipedia.org/wiki/Internet_Explorer]. Initially not very successful, the version 2.0 was distributed for free (Netscape was only free for non-commercial use) and launched the so-called browser wars which were finally won by Microsoft in 1997 when Netscape was acquired by AOL. However, the win resulted in several years of monopoly charges for Microsoft and the open-sourcing of Mozilla (initially the codename for Netscape's development version) giving rise to Firefox and several other browsers.

1995 was a successful year for Microsoft, who released Windows 95 as well as MS Office 95 and Windows NT 3.51. Yet in the same year, Bob Young and Marc Ewing found possibly the most successful commercial Linux company, Red Hat. In the hardware world, it is the birth year of two well-known connector standards: USB and IEEE 1394, also known as FireWire (used extensively by Apple).

While Linux established itself as viable server system soon enough (especially as the software set known as LAMP used to power a large share of web servers since mid-90s), it did not become as successful as a desktop system. In late nineties however, a step to that direction was made by the foundation of the two major desktop environments in GNOME and KDE.

In 1998, Microsoft releases its next operating system, the Windows 98. Apple returned to the spotlight with their iMac, a novel design combining the case and the monitor of the personal computer. Mandrake (later Mandriva) is the first Linux distribution specifically meant for desktop use (at first using mostly KDE as its environment). The [3] raised briefly the hopes of many people, but the dreams came true only for a small minority.

In the turn of the year 1999/2000, Microsoft released Windows 2000 - despite extensive promotion, the initial reception was somewhat disappointing[45], forcing the company to follow up with Service Pack 1 rather soon. Moreover, the desktop-oriented replacement for Windows 98, the Windows ME, has been considered by many the worst release of Windows[46], forcing the company to speed up the development of the next release. However, the 2001 release of Windows XP, being one of the most successful releases, set the company back on the tracks.

The new century began well for Microsoft, having overcome the legal hassles and successfully released Windows XP and MS Office 2000. However, its competitors did not relax either - Apple developed their new Unix-based operating system family in OS X, and for the first time, Linux software displayed more serious ambition on desktop as well - the WordPerfect Office 2000 was the first major office suite released for Linux among other platforms, and Sun started to distribute their freshly acquired StarOffice 5.2 as a free download[47]. Moreover, in late 2000 Sun split their StarOffice into a commercial offering of the same name and a community project title OpenOffice.org (nowadays distributed as Apache OpenOffice), the latter becoming an usable solution in less than a year.

The New Millennium

The first decade of the century feature among other things

  • the wireless boom - wireless networks spread fast both as commercial offerings and as public services.
  • the rise of free and open-source software in developing countries - especially prominent examples were Chile, Peru and Venezuela[48].
  • laptop computers and notebooks becoming affordable for 'average people'
  • rapid spread of affordable broadband Internet connections
  • the dark side of networking - hijacking the computers of 'ordinary users' becomes a major problem
  • various regulative legislation proposed, some of which are considered threatening to overall freedom
  • recent developments point towards the 'post-desktop' era - stationary computers are outnumbered by mobile devices (laptops, notebooks, tablets and smartphones).

Some interesting examples from the last decade:

  • The SCO lawsuit 2003-2011 (could even continue in the future) - the claim by SCO Group that Linux kernel 2.4 contains some code belonging to them. Most sources agree that the motivation was to force IBM to buy out the company. Interesting factors include
    • for the better part of the suit, the software in question has been outdated and replaced by new 2.6 kernel series (i.e. is not in use anymore)
    • throughout the process, the suitor has not managed to identify the exact code in question
    • from time to time, the suitor appeared to have received new funding to continue the process
  • The software patent war in European Parliament 2004-2005 - the controversal EU directive proposal about whether software is patentable or not bounced several times between the European Parliament (majority opposing it) and the European Commission (supporting it), each time changing slightly. Finally, the proposal was overwhelmingly rejected in July 2005.
  • Ubuntu - starting in 2004, the Linux distribution backed by Mark Shuttleworth and Canonical Ltd. had a rapid rise to the top soon after its initial release. With a steady release cycle (twice a year) and orientation to ordinary computer users, it became 'THE Linux' for many and at times, was able to challenge the established desktop operating systems by Microsoft and Apple. However, some recent development have resulted in controversy and alienated some of its user base.
  • Netbooks - since 2007, the small, light and cheap notebook computers mostly meant for e-mail, notetaking and simple web surfing. It is interesting to note that they were initially dominated by Linux - due to the fact that the Microsoft operating system of the day (Vista) was unable to run on them. Microsoft reacted by extending the support of XP until their new release (Windows 7) with lesser requirements on hardware arrived. Recently, they are increasingly being challenged by tablets.
  • The Android operating system developed by Google-led Open Handset Alliance since 2007 and together with Apple iOS, successfully bridging the gaps between the phones, larger handheld devices and notebooks (a good example of the latter is the Asus Eee Pad Transformer).
  • iPad - first released in 2010, it has defined the tablet computer for many users.
  • ACTA and its countercampaign in 2012 - while Europe had not experienced 'Facebook revolutions' similar to the Arab Spring or the Occupy movement, the large-scale public outlash was still remarkable.

References

  1. IFRAH, G. The Universal History of Computing: From the Abacus to the Quantum Computer, John Wiley & Sons 2001. ISBN 0471396710
  2. http://www.antikythera-mechanism.gr/project/overview
  3. http://history-computer.com/MechanicalCalculators/Pioneers/Leonardo.html
  4. http://history-computer.com/MechanicalCalculators/Pioneers/Schickard.html
  5. http://history-computer.com/People/PascalBio.html
  6. http://www-history.mcs.st-andrews.ac.uk/Biographies/Oughtred.html
  7. http://mysite.du.edu/~jcalvert/tech/slidrul.htm
  8. http://www.computerhistory.org/babbage/
  9. http://www.youtube.com/watch?v=Lcedn6fxgS0
  10. http://www.well.com/~adatoole/PoeticalScience.htm
  11. http://ftp.arl.mil/~mike/comphist/eniac-story.html
  12. http://www.webcitation.org/query?id=1257001829419648
  13. http://www.cbi.umn.edu/collections/inv/cbi00001.html
  14. http://www.ivorcatt.com/47c.htm
  15. http://web.archive.org/web/20080318184915/http://www.crash-it.com/crash/index.php?page=73
  16. http://www.zib.de/zuse/Inhalt/Programme/Plankalkuel/Plankalkuel-Report/Plankalkuel-Report.htm
  17. http://www.agnesscott.edu/lriddle/women/hopper.htm
  18. http://loebner.net/Prizef/TuringArticle.html
  19. http://www.cs.ut.ee/~varmo/tday-polva/tyugu-slides.pdf
  20. http://hrsbstaff.ednet.ns.ca/debcampbell/01-HisPlan12/3-GF/EspionnageLabo/spiesInsideKGBSite.htm
  21. http://news.bbc.co.uk/2/hi/science/nature/1633972.stm
  22. http://www.wired.com/science/discoveries/news/2008/12/dayintech_1209
  23. http://www.catb.org/jargon/html/W/walking-drives.html
  24. http://www-03.ibm.com/ibm/history/exhibits/storage/storage_chrono20.html
  25. MOSCHOVITIS, C.J.P., POOLE, H., SCHUYLER, T., SENFT, T.M. History of the Internet: A Chronology, 1843 to the Present. ABC-Clio 1999, ISBN: 1576071189
  26. http://cm.bell-labs.com/cm/cs/who/dmr/hist.html
  27. http://www.pretext.com/mar98/features/story2.htm
  28. http://www.supercomp.org/sc97/inet_history97/readerrail1.htm
  29. http://www.acm.org/classics/apr96
  30. http://www.blinkenlights.com/classiccmp/gateswhine.html
  31. http://www.livinginternet.com/l/li.htm
  32. http://www.livinginternet.com/u/ui.htm
  33. http://www.ibiblio.org/TH/mud.html
  34. http://www.patersontech.com/Dos/Micronews/paterson04_10_98.htm
  35. http://www.vanwensveen.nl/rants/microsoft/IhateMS_1.html
  36. http://arstechnica.com/old/content/2005/12/total-share.ars/1
  37. http://web.archive.org/web/20071012051803/http://www.cnn.com/2007/TECH/09/18/emoticon.anniversary.ap/index.html
  38. http://www.wordstar.org/index.php/wordstar-history
  39. http://www.gnu.org/gnu/manifesto.html
  40. http://www.w3.org/History/1989/proposal.html
  41. http://www.zakon.org/robert/internet/timeline/
  42. http://groups.google.com/group/comp.os.minix/msg/b813d52cbc5a044b?dmode=source&pli=1
  43. http://www.usdoj.gov/atr/cases/exhibits/20.pdf
  44. http://cyber.law.harvard.edu/msdoj/transcript/summaries1.html
  45. http://www.zdnet.co.uk/news/it-strategy/2000/02/14/bugfest-win2000-has-63000-defects-2076967/
  46. http://www.pcworld.com/article/125772-2/the_25_worst_tech_products_of_all_time.html
  47. http://www.linuxplanet.com/linuxplanet/reviews/1844/1
  48. http://www.brod.com.br/files/helsinki.pdf


Additional reading

  • CARLTON, J. Apple: The Inside Story of Intrigue, Egomania, and Business Blunders, Harper Paperbacks 1998. ISBN: 0887309658
  • FREIBERGER, P., SWAINE, M. Fire in the Valley: The Making of The Personal Computer, 2nd ed. McGraw-Hill 2000. ISBN: 0071358927
  • GATES, B. The Road Ahead. 2nd Revised ed. Pearson Elt 2008. ISBN: 140587932
  • ISAACSON, W. Steve Jobs. Simon & Schuster 2011. ISBN: 1451648537
  • LEVY, S. Hackers: Heroes of the Computer Revolution - 25th Anniversary Edition. O'Reilly 2010. ISBN: 1449388396
  • MOODY, G. Rebel Code: Linux And The Open Source Revolution. Basic Books 2002. ISBN: 0738206709
  • VISE, D., MAISEED, M. The Google Story: For Google's 10th Birthday. Delacorte Press 2008. ISBN: 0385342721