Encyclopedia of Computer Science and Technology

504 webcamabout a 75 percent market share by 2001. However, a ratherstrong competitor later emerged in Firefox, and other browserssuch as Opera and Safari also have their supporters, whofeel those products are more agile, versatile, and perhaps moresecure than Internet Explorer.Some typical features of a modern Web browser include• navigation buttons to move forward and back throughrecently visited pages• tabs to switch between Web pages• a “history” panel allowing return to pages visited inrecent days• a search button that brings up the default searchengine (which can be chosen by the user)• the ability to save page as “favorites” or “bookmarks”for easy retrievalThe Browser as PlatformToday a Web user can view a live news broadcast, listen tomusic from a radio station, or view a document formatted tonear-print quality. All these activities are made possible by“helper” software (see plug-in) that gives the Web browserthe capability to load and display or play files in special formats.Examples include the Adobe PDF (Portable DocumentFormat) reader, the Windows Media Player, and RealPlayerfor playing video and audio content (see streaming).What makes the browser even more versatile is the abilityto load and run programs from Web sites (see Java).Java was highly touted starting in the mid-1990s, and someobservers believed that by making Web browsers into platformscapable of running any sort of software, there wouldbe less need for proprietary operating systems such asMicrosoft Windows. Microsoft has responded by trying toshift developers’ emphasis from Java to its proprietary technologycalled .NET. Meanwhile, the tools for making Webpages more versatile and interactive continue to proliferate,including later versions of HTML and XML (see Web pagedesign). This proliferation, as well as use of proprietaryextensions can cause problems in accessing Web sites fromolder or less-known browsers.The growing numbers of handheld or palm computers(see portable computers) are accompanied by scaleddownWeb browsers. These are generally controlled bytouch and have a limited display size, but can provideinformation useful to travelers such as driving directions,weather forecasts, and capsule news or stock summaries.Further ReadingBarker, Donald I., and Katherine T. Pinard. Microsoft InternetExplorer 7, Illustrated Essentials. Boston: Course Technology,2007.Browser Review. Available online. URL: http://www.yourhtmlsource.com/starthere/browserreview.html.Accessed August23, 2007.Firefox 2. Available online. URL: http://www.mozilla.com/en-US/firefox/. Accessed August 23, 2007.Opera Browser Home Page. Available online. URL: http://www.opera.com/. Accessed August 23, 2007.Ross, Blake. Firefox for Dummies. Hoboken, N.J.: Wiley, 2006.Windows Internet Explorer 7. Available online. URL: http://www.microsoft.com/windows/products/winfamily/ie/default.mspx. Accessed August 23, 2007.webcamThousands of real-time views of the world are available onthe Web. These include everything from the prosaic (a coffeemachine at MIT) to the international (a view of downtownParis or Tokyo) to the sublime (a Rocky Mountainsunset). All of these views are made possible thanks to theavailability of inexpensive digital cameras (see photography,digital).To create a basic webcam, the user connects a digitalcamera to a PC, usually via a USB cable. A program controlsthe camera, taking a picture at frequent intervals (perhapsevery 30 seconds or minute). The picture is received fromthe camera as a JPG (JPEG) file. The program then uploadsthe picture to the user’s Web page (usually using file transferprotocol, or ftp), replacing the previous picture. Usersconnected to the Web site can click to see the latest picture.Alternatively, a script running on the server can update thepicture automatically.History and ApplicationsOne of the earliest and most famous webcams was createdby Quentin Stafford-Fraser in 1991. He later recalled that heand his fellow “coffee club” members were tired of makingthe long trek to the coffee room at the Cambridge Universitycomputer laboratory. It seemed that more often thannot the life-giving brew so necessary to computer sciencehad already been consumed. So they rigged a video camera,connected it to a video capture card, and fed the imageinto the building’s local network. Now researchers workinganywhere in the building could get an updated image of thecoffee machine three times a minute. This wasn’t technicallya webcam. At the time the Web was just being developedby Tim Berners-Lee (see Berners-Lee, Tim). However,the camera was put on the Web in 1993, where it resideduntil 2001 when the laboratory housing the now-famouscoffee machine was moved.The webcam became a social phenomenon in 1996 whena college student named Jennifer Ringley started Jennicam,a webcam set up to make a continuing record of her dailylife available on the Web. There were soon many imitators.Apparently this use of Webcams taps into humans’ intensecuriosity about the details of each other’s lives—a curiositythat to some critics tips over into voyeurism and obsession.The popularity of such social webcams may have contributedto the “reality TV” phenomenon at the turn of the newcentury.Webcams have many practical applications, however.People on the road can log into the Web and check to makesure everything is okay at home. A webcam also makes aninexpensive monitor for checking on infants or toddlers inanother room, or checking on the behavior of a babysitter(“Nannycam”).Webcams can also serve an educational purpose. Theycan take viewers to remote volcanoes or the interior of an