Encyclopedia of Computer Science and Technology

statistics and computing 457named Linus Torvalds decided to write the kernel and integrateit with much of the existing GNU software. The resultwould become known as Linux, and today it is a popularoperating system that runs on many servers and workstations.While acknowledging Torvalds’s efforts, Stallmaninsists that the operating system is more properly calledGNU Linux, to reflect the large amount of GNU code itemploys.In recent years Stallman has best been known as a vigorousadvocate for free software (see open-source movement)and for creating alternative structures for controllingits distribution, such as the various forms of the GeneralPublic License (GPL). Stallman has been accused of beingrigid and abrasive, such as in his urging that certain terminologybe used, or, in the case of the phrase “intellectualproperty,” not used.Stallman has received a number of important awards,including the ACM Grace Hopper Award (1990), ElectronicFrontier Foundation Pioneer Award (1998), and a MacArthurFoundation fellowship (1990).Further ReadingFree Software Foundation. Available online. URL: http://www.fsf.org/. Accessed August 22, 2007.Stallman, Richard M. Free Software, Free Society: Selected Essaysof Richard M. Stallman. Boston: Free Software Foundation,2002.Williams, Sam. Free as in Freedom: Richard Stallman’s Crusade forFree Software. Sebastapol, Calif.: O’Reilly Media, 2002.standards in computingOne hallmark of the maturity of a technology is the developmentof a variety of kinds of standards that are acceptedby a majority of practitioners. There are several reasonswhy standards develop.Marketplace StandardsIn many cases, a particular product gains a prominentposition in an emerging market, and would-be competitorsadopt its interface and specifications. For example,the parallel port printer interface (and plug) developedby Centronics for its printers was adopted by virtually allprinter manufacturers. Since it would be impracticable forcomputer manufacturers to provide many different parallelconnectors on their machines, there was a clear marketadvantage in setting a standard. When a particular product(Centronics in this case) becomes that standard, it is mainlya matter of timing.Once a marketplace standard is established, manufacturersand consumers will generally not want products that areincompatible with it. When the IBM PC and its ISA expansioncard became the standard followed by many “clone”manufacturers, IBM discovered that even Big Blue floutedthe standard at its peril. When IBM came out with its MCA(Microchannel Architecture) in the late 1980s, the newmachines, although possessing some technical advances,did not sell as well as expected. Most people stayed withthe existing IBM standard and built upwardly compatiblemachines upon it.Official StandardsSome standards are developed by official bodies. For example,the International Standards Organization (ISO) has anelaborate formal process where panels of experts developstandards for a huge variety of technologies, including manyrelating to computing. In an increasingly global economy,international standards allow equipment (or software) fromone country to be used with that from another. For example,credit cards, phone cards, and “smart cards” around theworld have a common format established by ISO standards.(Standards specific to electrical and electronic engineeringare developed by a similar body, the International ElectrotechnicalCommission, or IEC.) Standards that have becomewidely accepted but are not yet official ISO standards takethe form of Publicly Available Specifications, or PAS. Governmentcontracts often specify ISO standards as well as avariety of other standards developed by various governmentagencies. The ISO 9001 standards apply specifically to computersystems, software, and its development.Evolution of StandardsThe extent of standardization within the broad informationtechnology (IT) industry varies widely among applications.Generally, things that have been established for a long time(meaning, in computing terms, a couple decades or so) arelikely to be well standardized. An example is the standardsfor character sets.For areas in which new applications are emerging, practitionerstend to have less interest (or patience) with the idea ofstandards. For example, the World Wide Web is still relativelynew, and standards for the operation of Web sites are emergingonly slowly. In this case, it is mainly concern about suchmatters as privacy protection that has encouraged the adoptionof standards for matters such as the secure transmissionof credit card information on-line or privacy policies regardingthe use of information obtained from Web users. Thepotential threat of government regulation often encouragesthe development of marketplace standards as an alternative.Technical societies such as the Institute for Electricaland Electronic Engineering (IEEE) and the World WideWeb Consortium are an important forum for the discussionand development of standards.Further ReadingDargan, P. A. Open Systems and Standards for Software ProductDevelopment. Norwood, Mass.: Artech House, 2005.Hoyle, David. ISO 9000 Quality Systems Handbook. 2nd. ed. Burlington,Mass.: Butterworth-Heinemann, 2006.“ISO IEC 90003 2004 Software Standard Translated into PlainEnglish.” Paxiom Research Group. Available online. URL:http://www.praxiom.com/iso-90003.htm. Accessed August22, 2007.Lund, Susan K., and John W. Walz. Practical Support for ISO 9001Software Project Documentation: Using IEEE Software EngineeringStandards. New York: Wiley, 2006.statistics and computingThe application of computing technology to the collectionand analysis of statistics is as old as computing itself. Indeed,