Encyclopedia of Computer Science and Technology

248 Internettransmission of a message, e-mail today has a highdegree of reliability (see e-mail).• Netnews (also called Usenet, for UNIX User Network)is in effect the world’s largest computer bulletinboard. It began in 1979, when Duke Universityand the University of North Carolina set up a simplemechanism for “posting” text files that could be readby other users. Today there are tens of thousands oftopical “newsgroups” and millions of messages (calledarticles). Although still impressive in its quantity ofcontent, many Web users now rely more on discussionforums based on Web pages (see netnews andnewsgroups).• Ftp (File Transport Protocol) enables the transfer ofone or more files between any two machines connectedto the Internet. This method of file transferhas been largely supplanted by the use of downloadlinks on Web pages, except for high-volume applications(where an ftp server is often operated “behindthe scenes” of a Web link). FTP is also used by Webdevelopers to upload files to a Web site (see filetransfer protocols).• Telnet is another fundamental service that broughtthe Internet much of its early utility. Telnet allows auser at one computer to log into another machine andrun a program there. This provided an early means forusers at PCs or workstations to, for example, accessthe Library of Congress catalog online. However, ifprogram and file permissions are not set properly onthe “host” system, telnet can cause security vulnerabilities.The telnet user is also vulnerable to havingIDs and passwords stolen, since these are transmittedas clear (unencrypted) text. As a result, some onlinesites that once supported telnet access now limitaccess to Web-based forms. (Another alternative is touse a program called “secure shell” or ssh, or to use atelnet client that supports encryption.)• gopher was developed at the University of Minnesotaand named for its mascot. Gopher is a system of serversthat organize documents or other files througha hierarchy of menus that can be browsed by theremote user. Gopher became very popular in the late1980s, only to be almost completely supplanted bythe more versatile World Wide Web.• WAIS (Wide Area Information Service) is a gatewaythat allows databases to be searched over the Internet.WAIS provided a relatively easy way to bringlarge data resources online. It, too, has largely beenreplaced by Web-based database services.• The World Wide Web as mentioned above, is nowthe main means for displaying and transferring informationof all kinds over the Internet. Its flexibility,relative ease of use, and ubiquity (with Web browsersavailable for virtually all platforms) has caused it tosubsume most earlier services. The utility of the Webhas been further enhanced by the development ofmany search engines that vary in thoroughness andsophistication (see World Wide Web and searchengine).• Streaming Media protocols allow for a flow of videoand/or audio content to users. Player applications forWindows and other operating systems, and growinguse of high-speed consumer Internet connections (seebroadband) have made it possible to present “live”TV and radio shows over the Internet.• E-commerce, having boomed in the late 1990s andcrashed in the early 2000s, continued to grow andproliferate later in the decade, finding new marketsand applications and spreading into the developingworld (see e-commerce).• Blogs and other forms of online writing have becomeprevalent among people ranging from elementaryschool students to corporate CEOs (see blogs andblogging).• Social networking sites such as MySpace and Facebookare also very popular, particularly among youngpeople (see social networking).• Wikis have become an important way to share andbuild on knowledge bases (see wikis and Wikipedia).• The integration of the Internet with traditional channelsof communications is proceeding rapidly (seepodcasting, Internet radio, and VoIP).Even as it begins to level off in the United States, worldwideInternet usage continues to grow rapidly. Asia now hasmore than twice as many users as North America, althoughthe latter still has more than five times the penetration(percentage of population).In the United States more than half of Internet usershave high-speed Internet connections (see broadband), andthe trend in other developed countries is similar. Broadbandis both required by and contributes to the appetite ofWeb users for music, streaming video, and other rich mediacontent (see streaming and music and video distribution,online).Now in its fourth decade, the Internet is not withoutdaunting challenges. A major one is security—see computercrime and security, computer virus, cyberterrorism,and information warfare. Users also wantprotection from privacy abusers and online predators (seeprivacy in the digital age, identity theft, phishingand spoofing, and cyberstalking and harassment).For other issues and challenges involving the Internet,see censorship and the Internet, Internet architectureand governance, Internet access policy, anddigital divide.In the longer term what we call the Internet today islikely to become so ubiquitous that people will no longerthink of it as a separate system or entity. Household appliances,cars, cell phones, televisions, and virtually everyother device used in daily life will communicate with otherdevices and with control systems using Internet protocols.