Tuesday, 22 January 2013

Information Data

Again, this subject has relevance to economics...
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Information technology (IT) is the use of computers and telecommunications equipment to store, retrieve, transmit and manipulate data.[1] The term is commonly used as a synonym for computers and computer networks, but it also encompasses other information distribution technologies such as television and telephones.[2] Several industries are associated with information technology, such as computer hardware, software, electronics, semiconductors, internet, telecom equipment and computer services.[2]
In a business context, the Information Technology Association of America has defined information technology (IT) as "the study, design, development, application, implementation, support or management of computer-based information systems".[3] The business value of information technology is to automate business processes, provide information for decision making, connect business with their customers, and provide productivity tools to increase efficiency. In an academic context, the Association for Computing Machinery defines it as "undergraduate degree programs that prepare students to meet the computer technology needs of business, government, healthcare, schools, and other kinds of organizations .... IT specialists assume responsibility for selecting hardware and software products appropriate for an organization, integrating those products with organizational needs and infrastructure, and installing, customizing, and maintaining those applications for the organization’s computer users. Examples of these responsibilities include the installation of networks; network administration and security; the design of web pages; the development of multimedia resources; the installation of communication components; the oversight of email systems; and the planning and management of the technology lifecycle by which an organization’s technology is maintained, upgraded, and replaced."[4]
Humans have been storing, retrieving, manipulating and communicating information since the Sumerians in Mesopotamia developed writing in about 3000 BC,[5] but the term "Information Technology" in its modern sense first appeared in a 1958 article published in the Harvard Business Review; authors Leavitt and Whisler commented that "the new technology does not yet have a single established name. We shall call it information technology (IT)."[6] Based on the storage and processing technology employed, it is possible to distinguish four distinct phases of IT development: pre-mechanical (3000 BC – 1450 AD), mechanical (1450–1840), electromechanical (1840–1940) and electronic.[5] This article focuses on the latter of those periods, which began in about 1940.


[edit] History of computers

Devices have been used to aid computation for thousands of years, probably initially in the form of a tally stick.[7] The Antikythera mechanism, dating from about the beginning of the first century BC, is generally considered to be the earliest known mechanical analog computer; it is also the earliest known geared mechanism.[8] Comparable geared devices did not emerge in Europe until the 16th century,[9] and it was not until 1645 that the first mechanical calculator capable of performing the four basic arithmetical operations was developed.[10]
Electronic computers, using either relays or valves, began to appear in the early 1940s. The electromechanical Zuse Z3, completed in 1941, was the world's first programmable computer, and by modern standards one of the first machines that could be considered a complete computing machine. Colossus, developed during the Second World War to decrypt German messages was the first electronic digital computer, but although programmable it was not general-purpose, being designed for a single task. Neither did it store its programs in memory; programming was carried out using plugs and switches to alter the internal wiring.[11] The first recognisably modern electronic digital stored-program computer was the Manchester Small-Scale Experimental Machine (SSEM), which ran its first program on 21 June 1948.[12]

[edit] Data storage

Early electronic computers such as Colossus made use of punched tape, a long strip of paper on which data was represented by a series of holes, a technology now obsolete.[13] Electronic data storage as used in modern computers dates from the Second World War, when a form of delay line memory was developed to remove the clutter from radar signals, the first practical application of which was the mercury delay line.[14] The first random-access digital storage device was the Williams tube, based on a standard cathode ray tube,[15] but the information stored in it and delay line memory was volatile in that it had to be continuously refreshed, and thus was lost once power was removed. The earliest form of non-volatile computer storage was the magnetic drum, invented in 1932[16] and used in the Ferranti Mark 1, the world's first commercially available general-purpose electronic computer.[17]
Most digital data today is still stored magnetically on devices such as hard disk drives, or optically on media such as CD-ROMs.[18] It has been estimated that the worldwide capacity to store information on electronic devices grew from less than 3 exabytes in 1986 to 295 exabytes in 2007,[19] doubling roughly every 3 years.[20]

[edit] Databases

Database management systems emerged in the 1960s to address the problem of storing and retrieving large amounts of data accurately and quickly. One of the earliest such systems was IBM's Information Management System (IMS),[21] which is still widely deployed more than 40 years later.[22] IMS stores data hierarchically,[21] but in the 1970s Ted Codd proposed an alternative relational storage model based on set theory and predicate logic and the familiar concepts of tables, rows and columns. The first commercially available relational database management system (RDBMS) was available from Oracle in 1980.[23]
All database management systems consist of a number of components that together allow the data they store to be accessed simultaneously by many users while maintaining its integrity. A characteristic of all databases is that the structure of the data they contain is defined and stored separately from the data itself, in a database schema.[21]
The extensible markup language (XML) has become a popular format for data representation in recent years. Although XML data can be stored in normal file systems, it is commonly held in relational databases to take advantage of their "robust implementation verified by years of both theoretical and practical effort".[24] As an evolution of the Standard Generalized Markup Language (SGML), XML's text-based structure offers the advantage of being both machine and human-readable.[25]

[edit] Data retrieval

The relational database model introduced a programming language independent Structured Query Language (SQL), based on relational algebra.[23]
The terms "data" and "information" are not synonymous. Anything stored is data, but it only becomes information when it is organised and presented meaningfully.[26] Most of the world's digital data is unstructured, and stored in a variety of different physical formats[27][a] even within a single organisation. Data warehouses began to be developed in the 1980s to integrate these disparate stores. They typically contain data extracted from various sources, including external sources such as the Internet, organised in such a way as to facilitate decision support systems (DSS).[28]

[edit] Data transmission

Data transmission has three aspects: transmission, propagation, and reception.[29]
XML has been increasingly employed as a means of data interchange since the early 2000s,[30] particularly for machine-oriented interactions such as those involved in web-oriented protocols such as SOAP,[25] describing "data-in-transit rather than ... data-at-rest".[30] One of the challenges of such usage is converting data from relational databases into XML Document Object Model (DOM) structures.[31]

[edit] Data manipulation

Hilbert and Lopez[19] identify the exponential pace of technological change (a kind of Moore's law): machines' application-specific capacity to compute information per capita roughly doubled every 14 months between 1986 and 2007; the per capita capacity of the world's general-purpose computers doubled every 18 months during the same two decades; the global telecommunication capacity per capita doubled every 34 months; the world's storage capacity per capita required roughly 40 months to double (every 3 years); and per capita broadcast information has doubled every 12.3 years.[19]
Massive amounts of data are stored worldwide every day, but unless it can be analysed and presented effectively it essentially resides in what have been called data tombs: "data archives that are seldom visited".[32] To address that issue, the field of data mining – "the process of discovering interesting patterns and knowledge from large amounts of data"[33] – emerged in the late 1980s.[34]

[edit] Commercial perspective

Worldwide IT spending forecast[35] (billions of U.S. dollars)
Category2012 spending2013 spending
Data Center Systems141147
Enterprise Software278296
IT Services881927
Telecom services1,6611,701

[edit] Ethics

The field of information ethics was established by mathematician Norbert Wiener in the 1940s.[36] Some of the ethical issues associated with the use of information technology include:[37]
  • Breaches of copyright by those downloading files stored without the permission of the copyright holders
  • Employers monitoring their employees' emails and other Internet usage
  • Unsolicited emails
  • Hackers accessing online databases
  • Web sites installing cookies or spyware to monitor a user's online activities

[edit] See also

[edit] References

  1. ^ "Format" refers to the physical characteristics of the stored data such as its encoding scheme; "structure" describes the organisation of that data.
  1. ^ Daintith, John, ed. (2009), "IT", A Dictionary of Physics, Oxford University Press, http://www.oxfordreference.com/views/ENTRY.html?subview=Main&entry=t83.e1592, retrieved 1 August 2012 (subscription required)
  2. ^ a b Chandler, Daniel; Munday, Rod, "Information technology", A Dictionary of Media and Communication (first ed.), Oxford University Press, http://www.oxfordreference.com/views/ENTRY.html?subview=Main&entry=t326.e1343, retrieved 1 August 2012 (subscription required)
  3. ^ Proctor 2011, preface.
  4. ^ The Joint Task Force for Computing Curricula 2005. Computing Curricula 2005: The Overview Report (pdf)
  5. ^ a b Butler, Jeremy G., "A History of Information Technology and Systems", University of Arizona, http://www.tcf.ua.edu/AZ/ITHistoryOutline.htm, retrieved 2 August 2012
  6. ^ Leavitt, Harold J.; Whisler, Thomas L. Whisler (1958), "Management in the 1980s", Harvard Business Review 11, http://hbr.org/1958/11/management-in-the-1980s
  7. ^ Schmandt-Besserat, D. (1981), "Decipherment of the earliest tablets", Science 211 (4479): 283–285, doi:10.1126/science.211.4479.283, PMID 17748027 (subscription required)
  8. ^ Wright 2012, p. 279
  9. ^ Childress 2000, p. 94
  10. ^ Chaudhuri 2004, p. 3
  11. ^ Lavington 1980
  12. ^ Enticknap, Nicholas (Summer 1998), "Computing's Golden Jubilee", Resurrection (The Computer Conservation Society) (20), ISSN 0958-7403, http://www.cs.man.ac.uk/CCS/res/res20.htm#d, retrieved 19 April 2008
  13. ^ Alavudeen & Venkateshwaran 2010, p. 178
  14. ^ Lavington 1998, p. 1
  15. ^ "Early computers at Manchester University", Resurrection (The Computer Conservation Society) 1 (4), Summer 1992, ISSN 0958-7403, http://www.cs.man.ac.uk/CCS/res/res04.htm#g, retrieved 19 April 2008
  16. ^ Universität Klagenfurt, ed., "Magnetic drum", Virtual Exhibitions in Informatics, http://cs-exhibitions.uni-klu.ac.at/index.php?id=222, retrieved 21 August 2011
  17. ^ The Manchester Mark 1, University of Manchester, http://www.digital60.org/birth/manchestercomputers/mark1/manchester.html, retrieved 24 January 2009
  18. ^ Wang & Taratorin 1999, pp. 4–5.
  19. ^ a b c Hilbert, Martin; López, Priscilla, "The World's Technological Capacity to Store, Communicate, and Compute Information", Science 332 (6025): 60–65, http://www.sciencemag.org/content/332/6025/60, retrieved 1 August 2012
  20. ^ "video animation on The World's Technological Capacity to Store, Communicate, and Compute Information from 1986 to 2010
  21. ^ a b c Ward & Dafoulas 2006, p. 2
  22. ^ Olofson, Carl W. (October 2009), "A Platform for Enterprise Data Services", IDC, http://public.dhe.ibm.com/software/data/sw-library/ims/idc-power-of-ims.pdf, retrieved 7 August 2012
  23. ^ a b Ward & Dafoulas 2006, p. 3
  24. ^ Pardede 2009, p. 2
  25. ^ a b Pardede 2009, p. 4
  26. ^ Kedar 2009, pp. 1–9
  27. ^ van der Aalst 2011, p. 2
  28. ^ Dyché 2000, pp. 4–6
  29. ^ Weik 2000, p. 361
  30. ^ a b Pardede 2009, p. xiii.
  31. ^ Lewis 2003, pp. 228–231.
  32. ^ Han, Kamber & Pei 2011, p. 5
  33. ^ Han, Kamber & Pei 2011, p. 8
  34. ^ Han, Kamber & Pei 2011, p. xxiii
  35. ^ "Forecast Alert: IT Spending, Worldwide, 4Q12 Update". Gartner. http://www.gartner.com/DisplayDocument?id=2291618. Retrieved 2 January 2013.
  36. ^ Bynum 2008, p. 9.
  37. ^ Reynolds 2009, pp. 20–21.
  • Alavudeen, A.; Venkateshwaran, N. (2010), Computer Integrated Manufacturing, PHI Learning, ISBN 978-81-203-3345-1
  • Bynum, Terrell Ward (2008), "Norbert Wiener and the Rise of Information Ethics", in van den Hoven, Jeroen; Weckert, John, Information Technology and Moral Philosophy, Cambridge University Press, ISBN 978-0-521-85549-5
  • Chaudhuri, P. Pal (2004), Computer Organization and Design, PHI Learning, ISBN 978-81-203-1254-8
  • Childress, David Hatcher (2000), Technology of the Gods: The Incredible Sciences of the Ancients, Adventures Unlimited Press, ISBN 978-0-932813-73-2
  • Dyché, Jill (2000), Turning Data Into Information With Data Warehousing, Addison Wesley, ISBN 978-0-201-65780-7
  • Han, Jiawei; Kamber, Micheline; Pei, Jian (2011), Data Minining: Concepts and Techniques (3rd ed.), Morgan Kaufman, ISBN 978-0-12-381479-1
  • Kedar, Seema (2009), Database Management Systems, Technical Publications, ISBN 978-81-8431-584-4
  • Lavington, Simon (1980), Early British Computers, Digital Press, ISBN 978-0-7190-0810-8
  • Lavington, Simon (1998), A History of Manchester Computers (2 ed.), The British Computer Society, ISBN 978-1-902505-01-5
  • Lewis, Bryn (2003), "Extraction of XML from Relational Databases", in Chaudhri, Akmal B.; Djeraba, Chabane; Unland, Rainer et al., XML-Based Data Management and Multimedia Engineering – EDBT 2002 Workshops, Springer, ISBN 978-3540001300
  • Pardede, Eric (2009), Open and Novel Issues in XML Database Applications, Information Science Reference, ISBN 978-1-60566-308-1
  • Proctor, K. Scott (2011), Optimizing and Assessing Information Technology: Improving Business Project Execution, John Wiley & Sons, ISBN 978-1-118-10263-3
  • Reynolds, George (2009), Ethics in Information Technology, Cengage Learning, ISBN 978-0-538-74622-9
  • van der Aalst, Wil M. P. (2011), Process Mining: Discovery, Conformance and Enhancement of Business Processes, Springer, ISBN 978-3-642-19344-6
  • Wang, Shan X.; Taratorin, Aleksandr Markovich (1999), Magnetic Information Storage Technology, Academic Press, ISBN 978-0-12-734570-3
  • Ward, Patricia; Dafoulas, George S. (2006), Database Management Systems, Cengage Learning EMEA, ISBN 978-1-84480-452-8
  • Weik, Martin (2000), Computer Science and Communications Dictionary, 2, Springer, ISBN 978-0-7923-8425-0
  • Wright, Michael T. (2012), "The Front Dial of the Antikythera Mechanism", in Koetsier, Teun; Ceccarelli, Marco, Explorations in the History of Machines and Mechanisms: Proceedings of HMM2012, Springer, pp. 279–292, ISBN 978-94-007-4131-7

[edit] Further reading

  • Allen, T., and M. S. Morton, eds. 1994. Information Technology and the Corporation of the 1990s. New York: Oxford University Press.
  • Shelly, Gary, Cashman, Thomas, Vermaat, Misty, and Walker, Tim. (1999). Discovering Computers 2000: Concepts for a Connected World. Cambridge, Massachusetts: Course Technology.
  • Webster, Frank, and Robins, Kevin. (1986). Information Technology—A Luddite Analysis. Norwood, NJ: Ablex.

[edit] External links

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