Encyclopedia of Computer Science and Technology

294 mashupsbefore you buy” software (see shareware), some of whichis trial versions of full-blown commercial products. Thelocal “mom and pop” PC software store has largely vanished,with software now marketed mainly by chain storessuch as Electronics Boutique or CompUSA, and increasingly,through Web-based stores, often established by thechains, as well as the giant on-line bookstore Amazon.com.Another trend impacting the traditional package modelof software delivery is the hosting and serving of applicationsonline (see application service provider) using asubscription model. Google has offered a free suite of officeand communications applications online, including componentsthat can be used off-line. This and other emergingofferings may portend further splitting of the softwaremarket into high-end or specialized applications on the onehand, and added-value or premium versions of free softwareon the other.Further ReadingCampbell-Kelly, Martin. From Airline Reservations to Sonic theHedgehog: A History of the Software Industry. Cambridge,Mass.: MIT Press, 2004.Computer History Museum. Software Industry SIG. “Preservingthe History of the Software Industry.” Available online. URL:http://www.softwarehistory.org/. Accessed August 14, 2007.Cusumano, Michael. The Business of Software: What Every Manager,Programmer, and Entrepreneur Must Know to Thrive andSurvive in Good Times and Bad. New York: Free Press, 2004.Hasted, Edward. Software that Sells: A Practical Guide to Developingand Marketing Your Software Project. Indianapolis: Wiley,2005.Plunkett, Jack W. Plunkett’s InfoTech Industry Almanac. Houston,Tex.: Plunkett Research, 2007.mashupsToday the creative world has blurred the boundaries thatonce separated works of art. Songs are sampled and remixedfrom earlier songs. Star Wars fans create new chapters inthe saga by remixing existing footage and adding their ownnew footage and effects. The fluidity and ease of manipulationof all digital data, regardless of its original source, hasmade it easier than ever before to reuse, repurpose, or reinventcontent. It is not surprising, then, that software itselfcan be mixed and matched to create new applications calledmashups.Mashups are new applications created by puttingtogether data or features from existing applications, such asmaps and databases. Many Web applications are designedto make their services available to other programs (see service-orientedarchitecture and Web 2.0). This can bedone at the programming level by providing an applicationprogramming interface (see api), or even through simplerfacilities that can be used easily by nonprogrammers.A number of major Web sites and applications provideresources for mashups, including Google (particularlyGoogle Maps), Amazon, eBay, Flickr, YouTube (image andvideo sharing), the “social bookmarking” site del.iciou.us,and many others. Some of these services (and third parties)have provided mashup editors to simplify the process ofcreating mashups.As a simple example, suppose one wants to create a mapdisplay showing rentals in San Francisco by neighborhood,color coded by rent range. Google Maps can generate mapsfor any area and plot points on them, given coordinates in astandard tag. Craigslist has rental ads including addresses.To create a mashup, a “screenscraper” can be used to extractaddresses and rents from the ads, and the colored pointscan then be plotted on a map of the city via Google.While the most common types of mashups are createdby and for ordinary users, mashup techniques can alsobe used in business applications. For example, data fromseveral sources (such as Web feeds [see rss]) or variousdatabases can be brought together and provided with aneasy-to-use interface (see digital dashboard).Mashups can also be considered to be an aspect of theemerging new information economy. Developers may befinding it in their interest to provide APIs and services suitablefor mashups because, in turn, the mashups increasethe use of the original program. By providing these services,developers are also contributing to a “digital commons”that benefits all.Further ReadingFeiler, Jesse. How to Do Everything with Web 2.0 Mashups.Emeryville, Calif.: McGraw Hill-Osborne, 2007.Google Mashup Editor. Available online. URL: http://code.google.com/gme/. Accessed October 1, 2007.“How to Create a Mashup.” Mashup Awards. Available online.URL: http://mashupawards.com/create/. Accessed October 1,2007.Lewis, Andre, et al. Beginning Google Maps Applications with Railsand Ajax: From Novice to Professional. Berkeley, Calif.: Apress,2007.Microsoft Popfly. Available online. URL: http://www.popfly.com/.Accessed October 1, 2007.QEDWiki (IBM). Available online. URL: http://services.alphaworks.ibm.com/qedwiki/.Accessed October 1, 2007.Yahoo! Pipes. Available online. URL: http://pipes.yahoo.com/pipes/. Accessed October 1, 2007.Yee, Raymond. Pro Web 2.0 Mashups: Remixing Data and Web Services.Berkeley, Calif.: Apress, 2008.mathematics of computingThe roots of modern computer science lie in an interest inrapid computation. Simple mechanical calculators (see calculator)may date back to ancient times; however, it is thework of mathematicians Blaise Pascal (1623–1662) and GottfriedLeibniz (1646–1716) that gave rise to the first practicalmechanical calculators. By the mid-19th century, CharlesBabbage (1791–1871) had conceptualized and designedmechanical computers that included the essential features(programs, processor, memory, input/output) of the moderndigital computer (see Babbage, Charles). His motivationwas the need for rapid, accurate calculation of statisticaltables made necessary by the manufacturing economy of theIndustrial Revolution. By the end of the century, the volumeof such data had increased to the point where mechanicalcalculators and tabulators (see Hollerith, Herman) hadbecome the only practical way to keep up.