Encyclopedia of Computer Science and Technology

Ritchie, Dennis 409services to quickly assemble a dossier of sensitive informationon any individual was greatly increased. Here we havea case where a powerful tool for productivity (the Internet)also becomes a facilitator for using the vulnerabilities inany one system to compromise others.In an increasingly networked and technologically-dependentworld, the anticipation and prevention of computerrisks has become very important. To the extent companiesmay be legally liable for the more direct forms of risk, thereis more incentive for them to devote resources to risk amelioration.However, many computer-related risks are at leastas much social as technological in nature, and are beyondthe scope of concern of any one company or organization.Social risks ultimately demand a broader social response.Technology itself can be used to help ameliorate technologicalrisks. Artificial intelligence techniques (see expertsystems and neural network) might be used improve theability of a system to adapt to unusual conditions. However,any such programming then becomes prone to bugs andrisks itself.So far, the most successful way to deal with the broadrange of computer risks has been through human collaborationas facilitated by the Internet. Through venues such asthe Risks Forum computer-mediated communications andcollaboration allows for the pooling of human intelligence inthe face of the growing complexity of human inventiveness.Further ReadingComp.risks [access via Google Groups]. Available online. URL:http://groups.google.com/group/comp.risks/topics. AccessedAugust 19, 2007.Glass, Robert L. Software Runaways: Monumental Software Disasters.Upper Saddle River, N.J.: Prentice Hall, 1997.Neumann, Peter G. Computer-Related Risks. Reading, Mass.: Addison-Wesley,1994.Peterson, Ivars. Fatal Defect: Chasing Killer Computer Bugs. NewYork: Vintage Books, 1996.Ritchie, Dennis(1941– )AmericanComputer ScientistTogether with Ken Thompson, Dennis Ritchie developedthe UNIX operating system and the C programming language—twotools that have had a tremendous impact onthe world of computing for three decades.Ritchie was born on September 9, 1941, in Bronxville,New York. He was exposed to communications technologyand electronics from an early age because his father wasdirector of the Switching Systems Engineering Laboratoryat Bell Laboratories. (Switching theory is closely akinto computer logic design.) Ritchie attended Harvard Universityand graduated with a B.S. in physics. However, bythen his interests had shifted to applied mathematics and inparticular, the mathematics of computation, which he laterdescribed as “the theory of what machines can possiblydo” (see computability and complexity). For his doctoralthesis he wrote about recursive functions (see recursion).Together with Ken Thompson, Dennis Ritchie developed the UNIXoperating system and the C programming language, two of themost important developments in the history of computing. (Photocourtesy of Lucent Technologies’ Bell Labs)This topic was proving to be important for the definition ofnew computer languages in the 1960s (see Algol).In 1967, however, Ritchie decided that he had had enoughof the academic world. Without finishing the requirementsfor his doctorate, he started work at Bell Labs, his father’semployer. Bell Labs has made a number of key contributionsto communications and information theory (see researchlaboratories in computing).By the late 1960s, computer operating systems hadbecome increasingly complex and unwieldy. As typified bythe commercially successful IBM System/360, the operatingsystem was proprietary, had many hardware-specific functionsand tradeoffs in order to support a family of upwardlycompatible computer models, and was designed with a topdownapproach.During his graduate studies, however, Ritchie hadencountered a different approach to designing an operatingsystem. A new system called Multics was being designedjointly by Bell Labs, MIT, and General Electric. Multics wasquite different from the batch-processing world of mainframes:It was intended to allow many users to share acomputer. He had also done some work with MIT’s Project