Information Science

From New World Encyclopedia
(Redirected from Information science)


The Ancient Library of Alexandria, an early form of information storage and retrieval.

Information science (also information studies) is an interdisciplinary science primarily concerned with the collection, classification, manipulation, storage, retrieval, and dissemination of information. Information science studies the application and usage of knowledge in organizations, and the interaction between people, organizations, and information systems. It is often (mistakenly) considered a branch of computer science. It is actually a broad, interdisciplinary field, incorporating not only aspects of computer science, but also library science, cognitive, and social sciences.

Information science focuses on understanding problems from the perspective of the stakeholders involved and then applying information (and other) technology as needed. In other words, it tackles systemic problems first rather than individual pieces of technology within that system. In this respect, information science can be seen as a response to technological determinism, the belief that technology "develops by its own laws, that it realizes its own potential, limited only by the material resources available, and must therefore be regarded as an autonomous system controlling and ultimately permeating all other subsystems of society."[1] Within information science, attention has been given in recent years to human–computer interaction, groupware, the semantic web, value sensitive design, iterative design processes, and to the ways people generate, use and find information.

Information science should not be confused with information theory, the study of a particular mathematical concept of information, or with library science, a field related to libraries which uses some of the principles of information science.

Information science and informatics

Some authors treat informatics as a synonym for information science. Because of the rapidly evolving, interdisciplinary nature of informatics, a precise meaning of the term "informatics" is presently difficult to pin down. Regional differences and international terminology complicate the problem. Some people note that much of what is called "Informatics" today was once called "Information Science" at least in fields such as Medical Informatics. However when library scientists began also to use the phrase "Information Science" to refer to their work, the term informatics emerged in the United States as a response by computer scientists to distinguish their work from that of library science, and in Britain as a term for a science of information that studies natural, as well as artificial or engineered, information-processing systems.

History

Early beginnings

Gottfried Wilhelm von Leibniz, a philosopher who made significant contributions to what is now called "information science."

Information science, in studying the collection, classification, manipulation, storage, retrieval and dissemination of information has origins in the common stock of human knowledge. Information analysis has been carried out by scholars at least as early as the time of the Abyssinian Empire with the emergence of cultural depositories, what is today known as libraries and archives.[2] Institutionally, information science emerged in the nineteenth century along with many other social science disciplines. As a science, however, it finds its institutional roots in the history of science, beginning with publication of the first issues of ‘‘Philosophical Transactions,’’ generally considered the first scientific journal, in 1665 by the Royal Society (London).

The institutionalization of science occurred throughout the eighteenth century. In 1731, Benjamin Franklin established the Library Company of Philadelphia, the first “public” library, which quickly expanded beyond the realm of books and became a center of scientific experiment, and which hosted public exhibitions of scientific experiments.[3] Academie de Chirurgia (Paris) published ‘‘Memoires pour les Chirurgiens,’’ generally considered to be the first medical journal, in 1736. The American Philosophical Society, patterned on the Royal Society (London), was founded in Philadelphia in 1743. As numerous other scientific journals and societies were founded, Alois Senefelder developed the concept of lithography for use in mass printing work in Germany in 1796.

Nineteenth century

Joseph Marie Jacquard

By the nineteenth century the first signs of information science emerged as separate and distinct from other sciences and social sciences but in conjunction with communication and computation. In 1801, Joseph Marie Jacquard invented a punched card system to control operations of the cloth weaving loom in France. It was the first use of "memory storage of patterns" system.[4] As chemistry journals emerge throughout the 1820s and 1830s,[5] Charles Babbage developed his "difference engine," the first step towards the modern computer, in 1822 and his "analytical engine” by 1834. By 1843, Richard Hoe developed the rotary press, and in 1844 Samuel Morse sent the first public telegraph message. By 1848, William F. Poole began the ‘‘Index to Periodical Literature,’’ the first general periodical literature index in the U.S.

In 1854, George Boole published ‘‘An Investigation into Laws of Thought…,’’ which laid the foundations for Boolean algebra, which is later used in information retrieval.[6] In 1860, a congress was held at Karlsruhe Technische Hochschule to discuss the feasibility of establishing a systematic and rational nomenclature for chemistry. The congress does not reach any conclusive results, but several key participants return home with Stanislao Cannizzaro's outline (1858), which ultimately convinced them of the validity of his scheme for calculating atomic weights.[7]

By 1865 the Smithsonian Institution began a catalog of current scientific papers, which became the ‘‘International Catalogue of Scientific Papers’’ in 1902.[8] The following year the Royal Society began publication of its ‘‘Catalogue of Papers’’ in London. In 1866, Christopher Sholes, Carlos Glidden, and S.W. Soule produced the first practical typewriter. By 1872, Lord Kelvin devised an analogue computer to predict the tides, and by 1875 Frank Baldwin was granted the first U.S. patent for a practical calculating machine that performs four arithmetic functions.[9] Alexander Graham Bell and Thomas Edison invented the phonograph and telephone in 1876 and 1877 respectively, and the American Library Association is founded in Philadelphia. By 1879, ‘‘Index Medicus’’ is first issued by the Library of the Surgeon General, U.S. Army, with John Shaw Billings as librarian, and later the library issues ‘‘Index Catalogue,’’ which achieves an international reputation as the most complete catalog of medical literature.[10]

European documentation

Paul Otlet, a founder of modern information science

As many other disciplines emerged in the late part of the nineteenth century, as well as several more scientific indexes to organize scholarly literature, so did European Documentation, which marked the earliest theoretical foundations of modern information science. Most information science historians cite Paul Otlet and Henri La Fontaine as the fathers of information science with the founding of the International Institute of Bibliography (IIB) in 1895.[11] However, “information science” as a term is not popularly used in academia until after World War II.[12]

Documentalists emphasized the utilitarian integration of technology and technique toward specific social goals. According to Ronald Day, “As an organized system of techniques and technologies, documentation was understood as a player in the historical development of global organization in modernity—indeed, a major player inasmuch as that organization was dependent on the organization and transmission of information.”[12] Otlet and Lafontaine (who won the Nobel Prize in 1913) not only envisioned later technical innovations but also projected a global vision for information and information technologies that speaks directly to postwar visions of a global “information society.” Otlet and Lafontaine established numerous organizations dedicated to standardization, bibliography, international associations, and consequently, international cooperation. These organizations were fundamental for ensuring international production in commerce, information, communication and modern economic development, and they later found their global form in such institutions as the League of Nations and the United Nations. Otlet designed the Universal Decimal Classification, based on Melville Dewey’s decimal classification system.[12]

Although he lived decades before computers and networks emerged, what he discussed prefigured what ultimately became the World Wide Web. His vision of a great network of knowledge was centered on documents and included the notions of hyperlinks, search engines, remote access, and social networks. (Obviously these notions were described by different names.)

Otlet not only imagined that all the world's knowledge should be interlinked and made available remotely to anyone (what he called an International Network for Universal Documentation), he also proceeded to build a structured document collection that involved standardized paper sheets and cards filed in custom-designed cabinets according to an ever-expanding ontology, an indexing staff which culled information worldwide from as diverse sources as possible, and a commercial information retrieval service which answered written requests by copying relevant information from index cards. Users of this service were even warned if their query was likely to produce more than 50 results per search.[12]

By 1937, documentation had formally been institutionalized, as evidenced by the founding of the American Documentation Institute (ADI), later called the American Society for Information Science and Technology.

Transition to modern information science

Vannevar Bush, a famous information scientist, 1940.

With the 1950s came an increasing awareness of the potential of automatic devices for literature searching and information storage and retrieval. As these concepts grew in magnitude and potential, so did the variety of information science interests. By the 1960s and 70s, there was a move from batch processing to online modes, from mainframe to mini and micro computers. Additionally, traditional boundaries among disciplines began to fade and many information science scholars joined with library programs. Furthermore, they began to incorporate disciplines in the sciences, humanities and social sciences, as well as other professional programs, such as law and medicine in their curriculum. By the 1980s, large databases, such as Grateful Med at the National Library of Medicine, and user-oriented services such as Dialog and Compuserve, were for the first time accessible by individuals from their personal computers. The 1980s also saw the emergence of numerous Special Interest Groups to respond to the changes. By the end of the decade, Special Interest Groups were available involving non-print media, social sciences, energy and the environment, and community information systems. Today, information science largely examines technical bases, social consequences, and theoretical understanding of online databases, widespread use of databases in government, industry, and education, and the development of the Internet and World Wide Web.

Important historical figures

  • Tim Berners-Lee
  • John Shaw Billings
  • George Boole
  • Suzanne Briet
  • Michael Buckland
  • Vannevar Bush
  • Melville Dewey
  • Luciano Floridi

Topics in information science

Data modeling

Data modeling is the process of creating a data model by applying a data model theory to create a data model instance. A data model theory is a formal data model description. See database model for a list of current data model theories.

When data modeling, one is structuring and organizing data. These data structures are then typically implemented in a database management system. In addition to defining and organizing the data, data modeling will impose (implicitly or explicitly) constraints or limitations on the data placed within the structure.

Managing large quantities of structured and unstructured data is a primary function of information systems. Data models describe structured data for storage in data management systems such as relational databases. They typically do not describe unstructured data, such as word processing documents, email messages, pictures, digital audio, and video.

Document management

Document management and engineering is a computer system (or set of computer programs) used to track and store electronic documents and/or images of paper documents. Document management systems have some overlap with Content Management Systems, Enterprise Content Management Systems, Digital Asset Management, Document imaging, Workflow systems, and Records Management systems.

Groupware

Groupware is software designed to help people involved in a common task achieve their goals. Collaborative software is the basis for computer supported cooperative work.

Such software systems as email, calendaring, text chat, wiki belong in this category. It has been suggested that Metcalfe's law—the more people who use something, the more valuable it becomes—applies to such software.

The more general term social software applies to systems used outside the workplace, for example, online dating services and social networks like Friendster. The study of computer-supported collaboration includes the study of this software and social phenomena associated with it.

Human-computer interaction

Human-computer interaction (HCI), alternatively man-machine interaction (MMI) or computer–human interaction (CHI), is the study of interaction between people (users) and computers. It is an interdisciplinary subject, relating computer science with many other fields of study and research. Interaction between users and computers occurs at the user interface (or simply interface), which includes both software and hardware, for example, general purpose computer peripherals and large-scale mechanical systems such as aircraft and power plants.

Information architecture

Information architecture is the practice of structuring information (knowledge or data) for a purpose. These are often structured according to their context in user interactions or larger databases. The term is most commonly applied to Web development, but also applies to disciplines outside of a strict Web context, such as programming and technical writing. Information architecture is considered an element of user experience design.

The term information architecture describes a specialized skill set which relates to the management of information and employment of informational tools. It has a significant degree of association with the library sciences. Many library schools now teach information architecture.

An alternate definition of information architecture exists within the context of information system design, in which information architecture refers to data modeling and the analysis and design of the information in the system, concentrating on entities and their interdependencies. Data modeling depends on abstraction; the relationships between the pieces of data is of more interest than the particulars of individual records, though cataloging possible values is a common technique. The usability of human-facing systems, and standards compliance of internal ones, are paramount.

Information ethics

Information ethics is the field that investigates the ethical issues arising from the development and application of information technologies. It provides a critical framework for considering moral issues concerning informational privacy, moral agency (for example, whether artificial agents may be moral), new environmental issues (especially how agents should one behave in the infosphere), problems arising from the life-cycle (creation, collection, recording, distribution, processing, and so on) of information (especially ownership and copyright, digital divide). Information Ethics is therefore strictly related to the fields of computer ethics (Floridi, 1999) and the philosophy of information.

Dilemmas regarding the life of information are becoming increasingly important in a society that is defined as "the information society." Information transmission and literacy are essential concerns in establishing an ethical foundation that promotes fair, equitable, and responsible practices. Information ethics broadly examines issues related to, among other things, ownership, access, privacy, security, and community.

Information technology affects fundamental rights involving copyright protection, intellectual freedom, accountability, and security.

Professional codes offer a basis for making ethical decisions and applying ethical solutions to situations involving information provision and use which reflect an organization’s commitment to responsible information service. Evolving information formats and needs require continual reconsideration of ethical principles and how these codes are applied. Considerations regarding information ethics influence personal decisions, professional practice, and public policy.

Information retrieval

Information retrieval (IR), often studied in conjunction with information storage, is the science of searching for information in documents, searching for documents themselves, searching for metadata which describe documents, or searching within databases, whether relational stand-alone databases or hypertextually-networked databases such as the World Wide Web. There is a common confusion, however, between data retrieval, document retrieval, information retrieval, and text retrieval, and each of these has its own bodies of literature, theory, praxis and technologies. IR is, like most nascent fields, interdisciplinary, based on computer science, mathematics, library science, information science, cognitive psychology, linguistics, statistics, physics.

Automated IR systems are used to reduce information overload. Many universities and public libraries use IR systems to provide access to books, journals, and other documents. IR systems are often related to object and query. Queries are formal statements of information needs that are put to an IR system by the user. An object is an entity which keeps or stores information in a database. User queries are matched to objects stored in the database. A document is, therefore, a data object. Often the documents themselves are not kept or stored directly in the IR system, but are instead represented in the system by document surrogates.

Information society

Information society is a society in which the creation, distribution, diffusion, use, and manipulation of information is a significant economic, political, and cultural activity. The knowledge economy is its economic counterpart whereby wealth is created through the economic exploitation of understanding.

Specific to this kind of society is the central position information technology has for production, economy, and society at large. Information society is seen as the successor to industrial society. Closely related concepts are the post-industrial society (Daniel Bell), post-fordism, post-modern society, knowledge society, Telematic Society, Information Revolution, and network society (Manuel Castells).

Information systems

Information systems is the discipline concerned with the development, use, application and influence of information technologies. An information system is a technologically implemented medium for recording, storing, and disseminating linguistic expressions, as well as for drawing conclusions from such expressions.

The technology used for implementing information systems by no means has to be computer technology. A notebook in which one lists certain items of interest is, according to that definition, an information system. Likewise, there are computer applications that do not comply with this definition of information systems. Embedded systems are an example. A computer application that is integrated into clothing or even the human body does not generally deal with linguistic expressions. One could, however, try to generalize Langefors' definition so as to cover more recent developments.

Intellectual property

Intellectual property (IP) is a disputed umbrella term for various legal entitlements which attach to certain names, written and recorded media, and inventions. The holders of these legal entitlements are generally entitled to exercise various exclusive rights in relation to the subject matter of the IP. The term intellectual property links the idea that this subject matter is the product of the mind or the intellect together with the political and economical notion of property. The close linking of these two ideas is a matter of some controversy. It is criticized as "a fad" by Mark Lemley of Stanford Law School and by Richard Stallman of the Free Software Foundation as an "overgeneralization" and "at best a catch-all to lump together disparate laws."[13]

Intellectual property laws and enforcement vary widely from jurisdiction to jurisdiction. There are inter-governmental efforts to harmonize them through international treaties such as the 1994 World Trade Organization (WTO) Agreement on Trade-Related Aspects of Intellectual Property Rights (TRIPs), while other treaties may facilitate registration in more than one jurisdiction at a time. Enforcement of copyright, disagreements over medical and software patents, and the dispute regarding the nature of "intellectual property" as a cohesive notion[13] have so far prevented the emergence of a cohesive international system.

Knowledge management

Knowledge management comprises a range of practices used by organizations to identify, create, represent, and distribute knowledge for reuse, awareness, and learning across the organizations.

Knowledge Management programs are typically tied to organizational objectives and are intended to lead to the achievement of specific outcomes, such as shared intelligence, improved performance, competitive advantage, or higher levels of innovation.

Knowledge transfer (one aspect of Knowledge Management) has always existed in one form or another. Examples include on-the-job peer discussions, formal apprenticeship, corporate libraries, professional training, and mentoring programs. However, since the late twentieth century, additional technology has been applied to this task.

Knowledge engineering

Knowledge engineering (KE), often studied in conjunction with knowledge management, refers to the building, maintaining and development of knowledge-based systems. It has a great deal in common with software engineering, and is related to many computer science domains such as artificial intelligence, databases, data mining, expert systems, decision support systems and geographic information systems. Knowledge engineering is also related to mathematical logic, as well as strongly involved in cognitive science and socio-cognitive engineering where the knowledge is produced by socio-cognitive aggregates (mainly humans) and is structured according to our understanding of how human reasoning and logic works.

Semantic web

Semantic Web is an evolving extension of the World Wide Web in which web content can be expressed not only in natural language, but also in a form that can be understood, interpreted and used by software agents, thus permitting them to find, share and integrate information more easily.[14] It derives from W3C director Tim Berners-Lee's vision of the Web as a universal medium for data, information, and knowledge exchange.

At its core, the Semantic Web comprises a philosophy,[15] a set of design principles,[16] collaborative working groups, and a variety of enabling technologies. Some elements of the Semantic Web are expressed as prospective future possibilities that have yet to be implemented or realized.[14] Other elements of the Semantic Web are expressed in formal specifications. Some of these include Resource Description Framework (RDF), a variety of data interchange formats (for example, RDF/XML, N3, Turtle, and notations such as RDF Schema (RDFS) and the Web Ontology Language (OWL). All of which are intended to formally describe concepts, terms, and relationships within a given problem domain.

Usability engineering

Usability engineering is a subset of human factors that is specific to computer science and is concerned with the question of how to design software that is easy to use. It is closely related to the field of human-computer interaction and industrial design. The term "usability engineering" (UE) (in contrast to other names of the discipline, like interaction design or user experience design) tends to describe a pragmatic approach to user interface design which emphasizes empirical methods and operational definitions of user requirements for tools. Extending as far as International Standards Organization-approved definitions usability is considered a context-dependent agreement of the effectiveness, efficiency and satisfaction with which specific users should be able to perform tasks. Advocates of this approach engage in task analysis, then prototype interface designs and conduct usability tests. On the basis of such tests, the technology is (ideally) re-designed or (occasionally) the operational targets for user performance are revised.

User-centered design

User-centered design is a design philosophy and a process in which the needs, wants, and limitations of the end user of an interface or document are given extensive attention at each stage of the design process. User-centered design can be characterized as a multi-stage problem solving process that not only requires designers to analyze and foresee how users are likely to use an interface, but to test the validity of their assumptions with regards to user behaviour in real world tests with actual users. Such testing is necessary as it is often very difficult for the designers of an interface to understand intuitively what a first-time user of their design experiences, and what each user's learning curve may look like.

The chief difference from other interface design philosophies is that user-centered design tries to optimize the user interface around how people can, want, or need to work, rather than forcing the users to change how they work to accommodate the system or function.

XML

XML is a W3C-recommended general-purpose markup language that supports a wide variety of applications. XML languages or "dialects" may be designed by anyone and may be processed by conforming software. XML is also designed to be reasonably human-legible, and to this end, terseness was not considered essential in its structure. XML is a simplified subset of Standard Generalized Markup Language (SGML). Its primary purpose is to facilitate the sharing of data across different information systems, particularly systems connected via the Internet[17] Formally defined languages based on XML (such as RSS, MathML, GraphML, XHTML, Scalable Vector Graphics, MusicXML, and thousands of other examples) allow diverse software to reliably understand information formatted and passed in these languages.

Research

Many universities have entire schools or departments devoted to the study of information science, while numerous information science scholars can be found in disciplines such as communication, law, sociology, computer science, and library science to name a few. (See List of I-Schools and List of library and information science programs.)

Research methods

Information science has similar research methods to other social sciences:

Archival research
Facts or factual evidences from a variety of records are compiled.
Content analysis
The contents of books and mass media are analyzed to study how people communicate and the messages people talk or write about.
Case study
A specific set of circumstances or a group (the "case") is analyzed according to a specific goal of study. Generally, case studies are used to characterize a trend or development; they have weak generalizability.
Historical method
This involves a continuous and systematic search for the information and knowledge about past events related to the life of a person, a group, society, or the world.
Interviews
The researcher obtains data by interviewing people. If the interview is non-structured, the researcher leaves it to the interviewee (also referred to as the respondent or the informant) to guide the conversation.
Life history
This is the study of the personal life of a person. Through a series of interviews, the researcher can probe into the decisive moments in their life or the various influences on their life.
Longitudinal study
This is an extensive examination of a specific group over a long period of time.
Observation
Using data form the senses, one records information about social phenomenon or behavior. Qualitative research relies heavily on observation, although it is in a highly disciplined form.
Participant observation
As the name implies, the researcher goes to the field (usually a community), lives with the people for some time, and participates in their activities in order to know and feel their culture.

Notes

  1. Technological Determinism Web Dictionary of Cybernetics and Systems. Retrieved December 23, 2020.
  2. John Willis Clark, The Care Of Books: An Essay On The Development Of Libraries And Their Fittings, From The Earliest Times To The End Of The Eighteenth Century (Cambridge: Cambridge University Press, 1901).
  3. Margaret Barton Korty, “Benjamin Franklin and Eighteenth Century American Libraries,” ‘‘Transactions of the American Philosophical Society’’ 55(9) (1965).
  4. F. Reichman, "Notched Cards" in R. Shaw (ed.), The State of the Library Art (New Brunswick, NJ: Rutgers, The State University, Graduate School of Library Service, 1960).
  5. J.P. Emard, "An information science chronology in perspective," Bulletin of the American Society for Information Science 2(8): 51-56.
  6. E.S. Smith, "On the shoulders of giants: From Boole to Shannon to Taube: The origins and development of computerized information from the mid-19th century to the present," Information Technology and Libraries 12(2), 217-226.
  7. H. Skolnik, "Milestones in chemical information science: Award symposium on contributions of the Division of Chemical Literature (Information) to the Chemical Society," Journal of Chemical Information and Computer Science, 16(4) (1976): 187-193.
  8. B.W. Adkinson, "Federal government’s support of information activities: A historical sketch," Bulletin of the American Society for Information Science 2(8) (1976): 24-26.
  9. J.P. Emard, "An information science chronology in perspective," Bulletin of the American Society for Information Science, 2(8) (1976): 51-56.
  10. D.M. Schullian and F.B. Rogers, "The National Library of Medicine I," Library Quarterly 28(1) (1958): 1-17.
  11. W.B. Rayward, "International federation for information and documentation," In W.A. Wiegand and D. G. Davis Jr. (eds.), The Encyclopedia of Library History (New York: Routledge, 1994).
  12. 12.0 12.1 12.2 12.3 Ronald Day, Modern Invention of Information (Carbondale, IL: Southern Illinois University Press, 2001).
  13. 13.0 13.1 Richard Stallman, Did You Say "Intellectual Property"? It's a Seductive Mirage Retrieved December 23, 2020.
  14. 14.0 14.1 W3C, W3C Semantic Web Frequently Asked Questions Retrieved December 23, 2020.
  15. W3C, Semantic Web Activity Statement Retrieved December 23, 2020.
  16. W3C, Architectural and philosophical points. Retrieved December 23, 2020.
  17. W3C, Extensible Markup Language (XML) 1.0 (Fifth Edition)—Origin and Goals. Retrieved December 23, 2020.

References
ISBN links support NWE through referral fees

  • Clark, John Willis. The Care Of Books: An Essay On The Development Of Libraries And Their Fittings, From The Earliest Times To The End Of The Eighteenth Century. Cambridge: Cambridge University Press, 1901.
  • Cleveland, Harlan. The Knowledge Executive Leadership in an Information Society. New York: Truman Talley Books, 1985. ISBN 978-0525243076.
  • Davis, Charles Hargis, and James E. Rush. Guide to Information Science. Westport, CN: Greenwood Press, 1979. ISBN 978-0313209826.
  • Day, Ronald. Modern Invention of Information. Carbondale, IL: Southern Illinois University Press, 2001. ISBN 978-0809323906
  • Khosrowpour, Mehdi. Encyclopedia of Information Science and Technology. Hershey, PA: Idea Group Reference, 2005. ISBN 978-1591407942.
  • Luenberger, David G. Information Science. Princeton: Princeton University Press, 2006. ISBN 9780-691124186.
  • Norton, Melanie. Introductory Concepts in Information Science. ASIS monograph series. Medford, NJ: Published for the American Society for Information Science by Information Today, 2000. ISBN 978-1573870870.
  • Rubin, Richard. Foundations of Library and Information Science. New York: Neal-Schuman Publishers, 2004. ISBN 978-1555705183.
  • Saracevic, Tefko. Introduction to Information Science. New York: R.R. Bowker Co, 1970. ISBN 978-0835203135.
  • Shaw, R. (ed.). The State of the Library Art . New Brunswick, NJ: Rutgers, The State University, Graduate School of Library Service, 1960.
  • Wiegand, Wayne A., and Donald G. Davis Jr. (eds.). The Encyclopedia of Library History. New York: Routledge, 1994. ISBN 978-0824057879

External links

All links retrieved December 23, 2020.

Credits

New World Encyclopedia writers and editors rewrote and completed the Wikipedia article in accordance with New World Encyclopedia standards. This article abides by terms of the Creative Commons CC-by-sa 3.0 License (CC-by-sa), which may be used and disseminated with proper attribution. Credit is due under the terms of this license that can reference both the New World Encyclopedia contributors and the selfless volunteer contributors of the Wikimedia Foundation. To cite this article click here for a list of acceptable citing formats.The history of earlier contributions by wikipedians is accessible to researchers here:

The history of this article since it was imported to New World Encyclopedia:

Note: Some restrictions may apply to use of individual images which are separately licensed.