INFORMATION TECHNOLOGY KEY CONCEPTS Corporate applications are well under way, ■ A wide variety of online Semantic Web applications are and consumer uses are emerging emerging, from Vodafone Live!’s mobile phone service to Boeing’s system for coordinating the work of vendors. ix years ago in this magazine, Tim Ber- that would make this vision come true: a com- ners-Lee, James Hendler and Ora Las- mon language for representing data that could ■ Scientific researchers are devel- sila unveiled a nascent vision of the be understood by all kinds of software agents; oping some of the most advanced S Semantic Web: a highly interconnected network ontologies—sets of statements—that translate applications, including a system that pinpoints genetic causes of of data that could be easily accessed and under- information from disparate databases into heart disease and another system stood by any desktop or handheld machine. common terms; and rules that allow software that reveals the early stages of in- They painted a future of intelligent software agents to reason about the information de- fluenza outbreaks. agents that would head out on the World Wide scribed in those terms. The data format, ontol- Web and automatically book flights and hotels ogies and reasoning software would operate ■ Companies and universities, working through the World Wide for our trips, update our medical records and like one big application on the World Wide Web Consortium, are developing give us a single, customized answer to a partic- Web, analyzing all the raw data stored in online standards that are making the Se- ular question without our having to search for databases as well as all the data about the text, mantic Web more accessible and information or pore through results. images, video and communications the Web easy to use. —The Editors They also presented the young technologies contained. Like the Web itself, the Semantic SLIMFILMS 90 SCIENTIFIC AMERICAN December 20 07 © 2007 SCIENTIFIC AMERICAN, INC. BY :: Lee Feigenbaum, Ivan Herman, Tonya Hongsermeier, Eric Neumann and Susie Stephens Web would grow in a grassroots fashion, only Web to enhance business-to-business interac- this time aided by working groups within the tions and to build the hidden data-processing World Wide Web Consortium, which helps to structures, or back ends, behind new consumer advance the global medium. services. And like an iceberg, the tip of this Since then skeptics have said the Semantic large body of work is emerging in direct con- se•man•tic web Web would be too difficult for people to under- sumer applications, too. [si-’man-tik ‘w˘eb] stand or exploit. Not so. The enabling technol- —noun ogies have come of age. A vibrant community Just below the Surface A set of formats and lan- of early adopters has agreed on standards that The Semantic Web is not different from the guages that find and ana- have steadily made the Semantic Web practical World Wide Web. It is an enhancement that gives lyze data on the World to use. Large companies have major projects the Web far greater utility. It comes to life when Wide Web, allowing con- sumers and businesses to under way that will greatly improve the effi- people immersed in a certain field or vocation, understand all kinds of use- ciencies of in-house operations and of scientific whether it be genetic research or hip-hop music, ful online information. research. Other firms are using the Semantic agree on common schemes for representing www.SciAm.com SCIENTIFIC AMERICAN 91 © 2007 SCIENTIFIC AMERICAN, INC. [CONSUMER APPLICATIONS] information they care about. As more groups develop these taxonomies, Semantic Web tools Combining Concepts allow them to link their schemes and translate Search engines on the World Wide Web cannot provide a single answer to a broad- their terms, gradually expanding the number of ranging question such as “Which television sitcoms are set in New York City?” people and communities whose Web software But a new Semantic Web engine called pediax can, by analyzing different concepts can understand one another automatically. (top, in approximated form) found on Wikipedia’s seven million online pages. Perhaps the most visible examples, though Pediax, which grew from the DBpedia project to extract information from Wiki- limited in scope, are the tagging systems that pedia, provides a clean result (bottom) that merges text and images. have flourished on the Web. These systems in- clude del.icio.us, Digg and the DOI system used Sitcoms set in NYC Find by publishers, as well as the sets of custom tags available on social sites such as MySpace and Concept 1: Concept 2: Concept 3: Flickr. In these schemes, people select common “Sitcoms” “Set In” “NYC” terms to describe information they find or post on certain Web sites. Those efforts, in turn, en- able Web programs and browsers to find and ●1 crudely understand the tagged information— such as finding all Flickr photographs of sunris- es and sunsets taken along the coast of the Pa- cific Ocean. Yet the tags within one system do not work on the other, even when the same term, such as “expensive,” is used. As a result, these systems cannot scale up to analyze all the infor- mation on the Web. ●2 The World Wide Web Consortium—an ad hoc organization of more than 400 companies and universities co-hosted by the Massachu- setts Institute of Technology in the U.S., the Eu- ●3 ropean Consortium for Informatics and Math- ematics in France, and Keio University in Ja- ) pan—has already released the Semantic Web laptop ●4 languages and technologies needed to cross such boundaries, and large companies are ex- ploiting them. For example, British Telecom has built a prototype online service to help its many vendors more effectively develop new products );COURTESY APPLE,OF ( INC. together. Boeing is exploring the technologies to more efficiently integrate the work of part- screenshot ners involved in airplane design. Chevron is ex- perimenting with ways to manage the life cycle of power plants and oil refineries. MITRE Cor- ●1 poration is applying Semantic Web tool kits to help the U.S. military interpret rules of engage- ment for convoy movements. The U.K.’s nation- ●2 al mapping agency, Ordnance Survey, uses the Semantic Web internally to more accurately and inexpensively generate geographic maps. 3 ● Other companies are improving the back-end );AGILE KNOWLEDGE ENGINEERING ANDSEMANTIC ( WEB ●4 operations of consumer services. Vodafone Live!, a multimedia portal for accessing ring illustration tones, games and mobile applications, is built on Semantic Web formats that enable subscribers to download content to their phones much faster than before. Harper’s Magazine has harnessed semantic READING-IKKANDALUCY ( 92 SCIENTIFIC AMERICAN December 20 07 © 2007 SCIENTIFIC AMERICAN, INC. ontologies on its Web site to present annotated timelines of current events that are automatical- ly linked to articles about concepts related to FRIEND OF A FRIEND those events. Joost, which is putting television Users of a grassroots, semantic social net- on the Web for free, is using Semantic Web soft- work system—Friend of a Friend—have cre- ware to manage the schedules and program ated a vocabulary that describes the person- guides that viewers use online. al information they want to post and finds common interests. The network Consumers are also beginning to use the data (logo shown) can also integrate information from isolated, commercial language and ontologies directly. One example systems such as MySpace and Facebook. See www.foaf-project.org is the Friend of a Friend (FOAF) project, a de- centralized social-networking system that is growing in a purely grassroots way. Enthusiasts Nokia are promoting open-source Semantic Web have created a Semantic Web vocabulary for de- frameworks—common tools for crafting pol- scribing people’s names, ages, locations, jobs ished programs. Oracle’s flagship commercial and relationships to one another and for finding database, 10g, used by thousands of corpora- common interests among them. FOAF users can tions worldwide, already supports RDF, and the post information and imagery in any format upgrade, 11g, adds further Semantic Web tech- they like and still seamlessly connect it all, which nology. The latest versions of Adobe’s popular MySpace and Facebook cannot do because their graphics programs such as Photoshop use the fields are incompatible and not open to transla- same technologies to manage photographs and tion. More than one million individuals have al- illustrations. Smaller vendors—among them ready interlinked their FOAF files, including us- Aduna Software, Altova, @semantics, Talis, ers of LiveJournal and TypePad, two popular OpenLink Software, TopQuadrant and Soft- Weblog services. ware AG—offer Semantic Web database pro- As these examples show, people are moving grams and ontology editors that are akin to the toward building a Semantic Web where rela- HTML browsers and editors that facilitated the tions can be established among any online piec- Web’s vibrant growth. Semantic Web sites can es of information, whether an item is a docu- now be built with virtually all of today’s major ment, photograph, tag, financial transaction, computer programming languages, including experiment result or abstract concept. The data Java, Perl and C++. language, called Resource Description Frame- We are still finding our way toward the grand work (RDF), names each item, and the relations vision of agents automating the mundane tasks among the items, in a way that allows comput- of our daily lives. But some of the most ad- ers and software to automatically interchange vanced progress is taking place in the life scienc- the information. Additional power comes from es and health care fields. Researchers in these ontologies and other technologies that create, disciplines face tremendous data-integration query, classify and reason about those relations challenges at almost every stage of their work.