Television (often abbreviated to TV, T.V.; sometimes called , telly or the tube, bloob tube or boob tube, or idiot box in British English) is a widely used telecommunication system for broadcasting and receiving moving pictures and sound over a distance. The term may also be used to refer specifically to a television set, programming or television transmission. The word is derived from mixed Latin and Greek roots, meaning "far sight": Greek tele (Ïá¿Î»Îµ), far, and Latin vision, sight (from video, vis- to see, or to view in the first person).
Since it first became commercially available from the late 1930s, the television set has become a common household communications device in homes and institutions, particularly in the first world, as a source of entertainment and news. Since the 1970s, video recordings on VCR tapes and later, digital playback systems such as DVDs, have enabled the television to be used to view recorded movies and other programs.
A television system may be made up of multiple components, so a screen which lacks an internal tuner to receive the broadcast signals is called a monitor rather than a television. A television may be built to receive different broadcast or video formats, such as high-definition television, or preferably referred to as (HDTV).Elements of a television system
OT-1471 Belweder, Poland, 1957 1. power switch / volume 2. brightness 3. pitch 4. vertical synchro 5. horizontal synchro 6. contrast 7. channel tuning 8. channel switch
OT-1471 Belweder, Poland, 1957
1. power switch / volume
2. brightness
3. pitch
4. vertical synchro
5. horizontal synchro
6. contrast
7. channel tuning
8. channel switch
The elements of a simple broadcast television system are:
* An image source. This is the electrical signal representing the visual image, and may be from a camera in the case of live images, a video tape recorder for playback of recorded images, or a film chain-telecine-flying spot scanner for transmission of motion pictures (films).
* A sound source. This is an electrical signal from a microphone or from the audio output of a video tape recorder or motion picture film scanner.
* A transmitter, which generates radio signals (radio waves) and encodes them with picture and sound information.
* An antenna coupled to the output of the transmitter for broadcasting the encoded signals.
* An antenna to receive the broadcast signals.
* A receiver (also called a tuner), which decodes the picture and sound information from the broadcast signals, and whose input is coupled to the antenna.
* A display device, which turns the electrical signals into visual images.
* An audio amplifier and loudspeaker, which turns electrical signals into sound waves (speech, music, and other sounds) to accompany the images.
Practical television systems include equipment for selecting different image sources, mixing images from several sources at once, insertion of pre-recorded video signals, synchronizing signals from many sources, and direct image generation by computer for such purposes as station identification. The facility for housing such equipment, as well as providing space for stages, sets, offices, etc., is called a television studio, and may be located many miles from the transmitter. Communication from the studio to the transmitter is accomplished via a dedicated cable or radio system.
Television signals were originally transmitted exclusively via land-based transmitters. The quality of reception varied greatly, dependent in large part on the location and type of receiving antenna. This led to the proliferation of large rooftop antennas to improve reception in the 1960s, replacing set-top dipole or "rabbit ears" antennas, which however remained popular. Antenna rotors, set-top controlled servo motors to which the mast of the antenna is mounted, to enable rotating the antenna such that it points to the desired transmitter, would also become popular.
In most cities today, cable television providers deliver signals over coaxial or fiber-optic cables for a fee. Signals can also be delivered by radio from satellites in geosynchronous orbit and received by parabolic dish antennas, which are comparatively large for analog signals, but much smaller for digital. Like cable providers, satellite television providers also require a fee, often less than cable systems. The affordability and convenience of digital satellite reception has led to the proliferation of small dish antennas outside many houses and apartments.
Digital systems may be inserted anywhere in the chain to provide better image transmission quality, reduction in transmission bandwidth, special effects, or security of transmission from reception by non-subscribers. A home today might have the choice of receiving analog or HDTV over the air, analog or digital cable with HDTV from a cable television company over coaxial cable, or even from the phone company over fiber optic lines. On the road, television can be received by pocket sized televisions, recorded on tape or digital media players, or played back on wireless phones (cell or "mobile" phones) over a high-speed or "broadband" internet connection.
[edit] Display technology
Digital video equipment in an edit suite
Digital video equipment in an edit suite
See also: Comparison of display technology, Liquid crystal display television, and Large-screen television technology
Thanks to the advances in display technology, there are now several kinds of video displays used in modern TV sets:
* CRT (cathode-ray tube): The most common screens were direct-view CRTs for up to roughly 100 cm (40 inch) (in 4:3 ratio) and 115 cm (45 inch) (in 16:9 ratio) diagonals. These are the least expensive, and are a refined technology that can still provide the best overall picture quality value. As they do not have a fixed native resolution, they are capable of displaying sources with different resolutions at the best possible image quality. The frame rate or refresh rate of a typical NTSC format CRT TV is 29.97 Hz, and for the PAL format, 25 Hz, both are scanned with two fields per frame in an interlaced fashion. A typical NTSC broadcast signal's visible portion has an equivalent resolution of about 640x480 pixels. It actually could be slightly higher than that, but the vertical blanking interval (VBI), allows other signals to be carried along with the broadcast.
* Rear projection (RPTV): Most very large screen TVs (to 100 inches 254 cm or more) use projection technology. Three types of projection systems are used in projection TVs: CRT-based, LCD-based, and DLP (reflective micromirror chip) -based, D-ILA and LCOS-based. Projection television has been commercially available since the 1970s, but at that time could not match the image sharpness of the CRT; current models are vastly improved, and offer a cost-effective large-screen display.
o A variation is a video projector, using similar technology, which projects onto a screen.
A modern Philips LCD TV
A modern Philips LCD TV
* Flat panel (LCD or plasma): Modern advances have brought flat panels to TV that use active matrix LCD or plasma display technology. Flat panel LCDs and plasma displays are as little as 25.4 mm (1 inch) thick and can be hung on a wall like a picture or put over a pedestal. Some models can also be used as computer monitors.
* LED technology has become one of the choices for outdoor video and stadium uses, since the advent of bright LEDs and driver circuits. LEDs enable scalable ultra-large flat panel video displays that other technologies may never be able to match in performance.
Each has its pros and cons. Flat panel LCD and plasma displays have a wide viewing angle (around 178 degrees) so they may best suited for a home theatre with a wide seating arrangement. Rear projection screens do not perform well in daylight or well-lit rooms and so are only suited to darker viewing areas.
[edit] Terminology for televisions
Pixel resolution is the amount of individual points known as pixels on a given screen. Use of the word pixel is fairly new, as it only dates to the introduction of the DVD digital display standard. Before the year 2000 horizontal lines of resolution was the standard method of measurement for analog video. For example, a VHS VCR might be described as having 250 lines of resolution as measured across a circle circumscribed in the center of the screen (approximately 440 pixels edge-to-edge).
A typical resolution of 720Ã480 means that the television display has 720 pixels across and 480 pixels on the vertical axis. The higher the resolution on a specified display the sharper the image. Contrast ratio is a measurement of the range between the brightest and darkest points on the screen.
The higher the contrast ratio, the better looking picture there is in terms of richness, deepness, and shadow detail. The brightness of a picture measures how vibrant and impacting the colors are. Measured in cd / m2 equivalent to the amount of candles required to power the image.
On the other hand, the so-called brightness and contrast adjustment controls on televisions and monitors are traditionally used to control different aspects of the picture display.
The brightness control shifts the black point, or shadow level, primarily affecting the contrast ratio or gamma of the image, while the contrast control primarily controls the image intensity or brightness.[1]
[edit] Transmission band
There are various bands on which televisions operate depending upon the country. The VHF and UHF signals in bands III to V are generally used. Lower frequencies do not have enough bandwidth available for television. Although the BBC initially used Band I VHF at 45 MHz, this frequency is (in the UK) no longer in use for this purpose. Band II is used for FM radio transmissions. Higher frequencies behave more like light and do not penetrate buildings or travel around obstructions well enough to be used in a conventional broadcast TV system, so they are generally only used for MMDS and satellite television, which uses frequencies from 2 to 12 GHz. TV systems in most countries relay the video as an AM (amplitude-modulation) signal and the sound as a FM (frequency-modulation) signal. An exception is France, where the sound is AM.
[edit] Aspect ratios
Aspect ratio refers to the ratio of the horizontal to vertical measurements of a television's picture. Mechanically scanned television as first demonstrated by John Logie Baird in 1926 used a 7:3 vertical aspect ratio, oriented for the head and shoulders of a single person in close-up.
Most of the early electronic TV systems from the mid-1930s onward shared the same aspect ratio of 4:3 which was chosen to match the Academy Ratio used in cinema films at the time. This ratio was also square enough to be conveniently viewed on round cathode-ray tubes (CRTs), which were all that could be produced given the manufacturing technology of the time. (Today's CRT technology allows the manufacture of much wider tubes, and the flat-screen technologies which are becoming steadily more popular have no technical aspect ratio limitations at all.) The BBC's television service used a more squarish 5:4 ratio from 1936 to 3 April 1950, when it too switched to a 4:3 ratio. This did not present significant problems, as most sets at the time used round tubes which were easily adjusted to the 4:3 ratio when the transmissions changed.
In the early 1950s, movie studios moved towards widescreen aspect ratios such as CinemaScope in an effort to distance their product from television. Although this was initially just a gimmick, widescreen is still the format of choice today and 4:3 aspect ratio movies are rare.
Yet the various television systems were not originally designed to be compatible with film at all. Traditional, narrow-screen movies are projected onto a television camera either so that the top of the screens line up to show facial features, or, for films with subtitles, the bottoms. What this means is that filmed newspapers or long captions filling the screen for explanation are cut off at each end. Similarly, while the frame rate of sound films is 24 per second, the screen scanning rate of the NTSC is 29.97 Hz (per second), which requires a complex scanning schedule. That of PAL and SECAM are 50 Hz, which means that films are shortened (and the sound is offkey) by scanning each frame twice for 25 per second.
The switch to digital television systems has been used as an opportunity to change the standard television picture format from the old ratio of 4:3 (1.33:1) to an aspect ratio of 16:9 (approximately 1.78:1). This enables TV to get closer to the aspect ratio of modern widescreen movies, which range from 1.66:1 through 1.85:1 to 2.35:1. There are two methods for transporting widescreen content, the most common of which uses what is called anamorphic widescreen format. This format is very similar to the technique used to fit a widescreen movie frame inside a 1.33:1 35 mm film frame. The image is compressed horizontally when recorded, then expanded again when played back. The anamorphic widescreen 16:9 format was first introduced via European PALPlus television broadcasts and then later on "widescreen" DVDs; the ATSC HDTV system uses straight widescreen format, no horizontal compression or expansion is used.
Recently "widescreen" has spread from television to computing where both desktop and laptop computers are commonly equipped with widescreen displays. There are some complaints about distortions of movie picture ratio due to some DVD playback software not taking account of aspect ratios; but this may subside as the DVD playback software matures. Furthermore, computer and laptop widescreen displays are in the 16:10 aspect ratio both physically in size and in pixel counts, and not in 16:9 of consumer televisions, leading to further complexity. This was a result of widescreen computer display engineers' assumption that people viewing 16:9 content on their computer would prefer that an area of the screen be reserved for playback controls, subtitles or their Taskbar, as opposed to viewing content full-screen.
[edit] Aspect ratio incompatibility
The television industry's changing of aspect ratios is not without difficulties, and can present a considerable problem.
Displaying a widescreen aspect (rectangular) image on a conventional aspect (square or 4:3) display can be shown:
* in "letterbox" format, with black horizontal bars at the top and bottom
* with part of the image being cropped, usually the extreme left and right of the image being cut off (or in "pan and scan", parts selected by an operator or a viewer)
* with the image horizontally compressed
A conventional aspect (square or 4:3) image on a widescreen aspect (rectangular with longer horizon) display can be shown:
* in "pillar box" format, with black vertical bars to the left and right
* with upper and lower portions of the image cut off (or in "tilt and scan", parts selected by an operator)
* with the image vertically compressed
A common compromise is to shoot or create material at an aspect ratio of 14:9, and to lose some image at each side for 4:3 presentation, and some image at top and bottom for 16:9 presentation. In recent years, the cinematographic process known as Super 35 (championed by James Cameron) has been used to film a number of major movies such as Titanic, Legally Blonde, Austin Powers, and Crouching Tiger, Hidden Dragon (see also: Films shot in Super 35). This process results in a camera-negative which can then be used to create both wide-screen theatrical prints, and standard "full screen" releases for television/VHS/DVD which avoid the need for either "letterboxing" or the severe loss of information caused by conventional "pan-and-scan" cropping.
[edit] Sound
Further information: NICAM, MTS, and Zweikanalton
[edit] Data
Further information: Teletext
[edit] The end of analog television broadcasting
Main article: Analogue switch-off
[edit] NTSC
In North America, the basic signal standards since 1941 have been compatible enough that even the oldest monochrome televisions can still receive color broadcasts in 2007. However, the United States Congress has passed a law which requires the cessation of all conventional television broadcast signals by February 2009. If the law is not changed again, then after that date all NTSC standard televisions, with analog-only tuners, will go dark unless fitted with digital ATSC tuners, and the spectrum previously occupied by those analog channels will be auctioned off by the United States' Federal Communications Commission for other uses. The analog cut-off date has been changed by Congress in the past.
[edit] PAL and SECAM
PAL and SECAM are expected not to be broadcast in Europe and Eurasia by the mid-2020s. PAL-M may have a similar decommissioning timeline.
The European Union has recommended its members to have closed down analogue terrestrial television by 2012. Luxembourg and the Netherlands had already completed their closedowns in 2006, and Finland and Sweden will have closed down their analogue broadcasts in 2007. Meanwhile, some countries may have difficulties making the 2012 deadline.
[edit] Television add-ons
The television was the first consumer mass market for video displays. Today there are many television add-ons including video game consoles, VCRs, Set-top boxes for Cable, Satellite and DVB-T compliant Digital Television reception, DVD players, or Digital Video Recorders (including personal video recorders, PVRs). The add-on market continues to grow as new technologies are developed. Computers, the internet, and even pocket devices such as the iPod provide other ways to consume video content.
[edit] New developments
* Ambilightâ¢
* Broadcast flag
* CableCARDâ¢
* Digital Light Processing (DLP)
* Digital Rights Management (DRM)
* Digital television (DTV)
* Digital Video Recorders (DVR)
* Direct Broadcast Satellite TV (DBS)
* DVD and HD DVD standards
* Blu-ray Disc
* Flicker-free (100 Hz or 120 Hz, depending on country)
* High Definition TV (HDTV)
* High-Definition Multimedia Interface (HDMI)
* IPTV also know as Internet television
* Laser TV display technology
* LCD and plasma display flat screen TV
* SED display technology
* OLED display technology
* P2PTV
* Pay-per-view
* Personal video recorders (PVR)
* Picture-in-picture (PiP)
* Pixelplus
* Placeshifting
* Remote controls
* The Slingbox
* Timeshifting
* Video on-demand (VOD)
* Ultra High Definition Video (UHDV)
* Web TV
* Roll up Tv
Samsung LE26R41BD HDTV
Samsung LE26R41BD HDTV
A long screen television in Korea.
A long screen television in Korea.
[edit] Exterior designs
In the early days of television, cabinets were made of wood grain, however, they were phased out in the 1980s. There has been a modern comeback of woodgrain.[2][3]
[edit] Geographical usage
* Timeline of the introduction of television in countries
Main article: Geographical usage of television
[edit] Content
[edit] Programming
See also: Category:Television genres
Getting TV programming shown to the public can happen in many different ways. After production the next step is to market and deliver the product to whatever markets are open to using it. This typically happens on two levels:
1. Original Run or First Run – a producer creates a program of one or multiple episodes and shows it on a station or network which has either paid for the production itself or to which a license has been granted by the producers to do the same.
2. Syndication – this is the terminology rather broadly used to describe secondary programming usages (beyond original run). It includes secondary runs in the country of first issue, but also international usage which may or may not be managed by the originating producer. In many cases other companies, TV stations or individuals are engaged to do the syndication work, in other words to sell the product into the markets they are allowed to sell into by contract from the copyright holders, in most cases the producers.
In most countries, the first wave occurs primarily on free-to-air (FTA) television, while the second wave happens on subscription TV and in other countries. In the U.S., however, the first wave occurs on the FTA networks and subscription services, and the second wave travels via all means of distribution.
First run programming is increasing on subscription services outside the U.S., but few domestically produced programs are syndicated on domestic FTA elsewhere. This practice is increasing however, generally on digital-only FTA channels, or with subscriber-only first run material appearing on FTA.
Unlike the U.S., repeat FTA screenings of a FTA network program almost only occur on that network. Also, Affiliates rarely buy or produce non-network programming that is not centred around local events.
[edit] Advertising
Globe icon The examples and perspective in this section may not represent a worldwide view of the subject.
Please improve this article or discuss the issue on the talk page.
Since inception in the U.S. in 1940, TV commercials have become one of the most effective, most persuasive, and most popular methods of selling products of many sorts, especially consumer goods. U.S. advertising rates are determined primarily by Nielsen Ratings. The time of the day and popularity of the channel determine how much a television commercial can cost. For example, the highly popular American Idol can cost approximately $750,000 for a thirty second block of commercial time; while the same amount of time for the World Cup and the Super Bowl can cost several million dollars.
In recent years, the paid program or infomercial has become common, usually in lengths of 30 minutes or one hour. Some drug companies have even created "news" items for broadcast, paying program directors to use them.[4]
Some TV programs also weave advertisements into their shows, a practise begun in film and known as product placement. For example, a character could be drinking a certain kind of soda, going to a particular chain restaurant, or driving a certain make of car. (This is sometimes very subtle, where shows have vehicles provided by manufacturers for low cost, rather than wrangling them.) Sometimes a specific brand or trade mark, or music from a certain artist or group, is used. (This excludes guest appearances by artists, who perform on the show.)
[edit] Television genres
Television genres include a broad range of programming types that entertain, inform, and educate viewers. The most expensive entertainment genres to produce are usually drama and dramatic miniseries. However, other genres such as historical Western genres may also have high production costs.
Popular entertainment genres include action-oriented shows such as police, crime, detective dramas, horror or thriller shows. As well, there are also other variants of the drama genre, such as medical dramas and daytime Soap Operas. Sci-fi (Science fiction) shows can fall into either the drama category or the action category, depending on whether they emphasize philosophical questions or explosive space battles. Comedy is a popular genre which includes sitcoms (Situation Comedy) and animated shows for the adult demographic such as South Park.
The least expensive forms of entertainment programming are game shows, talk shows, variety shows, and reality TV. Game shows show contestants answering questions and solving puzzles to win prizes. Talk shows feature interviews with film, television and music celebrities and public figures. Variety shows feature a range of musical performers and other entertainers such as comedians and magicians introduced by a host or Master of Ceremonies. There is some crossover between some talk shows and variety shows, because leading talk shows often feature performances by bands, singers, comedians, and other performers in between the interview segments.
Reality TV shows show "regular" people (i.e., not actors) who are facing unusual challenges or experiences, ranging from arrest by police officers (COPS) to weight loss (The Biggest Loser). A variant version of reality shows depicts celebrities doing mundane activities such as going about their everyday life (The Osbournes) or doing manual labour jobs (Simple Life).
One of the television genres, the children's and youth genre is defined by the audience, rather than by the content of the programming. Children's programming includes animated programs aimed at the child demographic, documentaries for children, and music/variety shows targeted at kids. There is overlap between the children's/youth genre and other genres, such as the educational genre.
Television genres that aim to educate and inform viewers include educational shows, DIY programs on cooking, gardening, or home renovation, history shows, performing arts programs, and documentaries. Other genres which inform viewers include news, sports, and public affairs programming.
[edit] Social aspects
[edit] Technology trends
In its infancy, television was an ephemeral medium. Fans of regular shows planned their schedules so that they could be available to watch their shows at their time of broadcast. The term appointment television was coined by marketers to describe this kind of attachment.
The viewership's dependence on schedule lessened with the invention of programmable video recorders, such as the Videocassette recorder and the Digital video recorder. Consumers could watch programs on their own schedule once they were broadcast and recorded. Television service providers also offer video on demand, a set of programs which could be watched at any time.
Both mobile phone networks and the Internet are capable of carrying video streams. There is already a fair amount of Internet TV available, either live or as downloadable programs, and video sharing websites have become greatly popular.
The Japanese manufacturer Scalar has developed a very small TV-system attached to the eyeglasses, called "Teleglass T3-F".[5]
[edit] Suitability for audience
Almost since the medium's inception there have been charges that some programming is, in one way or another, inappropriate, offensive or indecent. Critics such as Jean Kilborne have claimed that television, as well as other mass media images, harm the self image of young girls. Other commentators such as Sut Jhally make the case that television advertisers in the U.S. deliberately try to equate happiness with the purchasing of products, despite studies which show that happiness for most people comes from non-material realms, such as warm friendships and feelings of connection to one's community.[6] George Gerbner has presented evidence that the frequent portrayals of crime, especially minority crime, has led to the Mean World Syndrome, the view among frequent viewers of television that crime rates are much higher than the actual data would indicate. In addition, a lot of television has been charged with presenting propaganda, political or otherwise, and being pitched at a low intellectual level.
[edit] Alleged dangers
The neutrality of this section is disputed.
Please see the discussion on the talk page.
See also: Media violence research
Paralleling television's growing primacy in family life and society, an increasingly vocal chorus of legislators, scientists and parents are raising objections to the uncritical acceptance of the medium. For example, the Swedish government imposed a total ban on advertising to children under twelve in 1991 (see advertising). Fifty years of research on the impact of television on children's emotional and social development demonstrate that there are clear connections between watching violence on television and engaging in aggressive or violent behavior.[7] In a recent study published in the journal Media Psychology, the research team demonstrated that the brain activation patterns of children viewing violence show that children are aroused by the violence (increased heart rates), demonstrate fear (activation of the amygdala-the fight or flight sensor in the brain) in response to the video violence, and store the observed violence in an area of the brain (the posterior cingulate) that is reserved for long-term memory of traumatic events.[8]
A 2002 article in Scientific American suggested that compulsive television watching, television addiction, was no different from any other addiction, a finding backed up by reports of withdrawal symptoms among families forced by circumstance to cease watching.[9] A longitudinal study in New Zealand involving 1000 people (from childhood to 26 years of age) demonstrated that "television viewing in childhood and adolescence is associated with poor educational achievement by 12 years of age". In other words, the more the child watched television, the less likely he or she was to finish school and enroll in a university.[10] A study published in the Journal of Sexuality Research and Social Policy concluded that parental television involvement was associated with greater body satisfaction among adolescent girls, less sexual experience amongst both male and female adolescents, and that parental television involvement may influence self-esteem and body image, in part by increasing parent-child closeness.[11] Numerous studies have been done on the relationship between TV viewing and school grades.[12]
One of the reasons people campaign against TV is because of the activities people are not doing during the time that they watch it. Many campaigners believe that using up 3.5 hours a day on TV (UK and American average) is not worthwhile. While only 3% of American minors own personal TV's, it is estimated that the daily viewing average among 12–17 yr olds exceeds 4 hours, with this figure being dramatically higher in parts of the United States.[citation needed]
[edit] Propaganda delivery
Audiovisual media, including television, is the second most effective means of communication available to the psychological operator. Effectiveness is based on seeing and hearing the persuasive message. These media are an excellent means of transmitting persuasive messages and eliciting a high degree of recall.[13]
Propaganda can exist on news, current affairs or talk show segments, as advertising or public-service announce "spots" or as long-running advertorials.[14]
[edit] Educational advantages
Despite this research, many media scholars today dismiss such studies as flawed. For one example of this school of thought, see David Gauntlett's article "Ten Things Wrong With the Media 'Effects' Model." Dimitri Christakis cites studies in which those who watched "Sesame Street" and other educational programs as preschoolers had higher grades, were reading more books, placed more value on achievement and were more creative. Similar, while those exposed to negative role models suffered, those exposed to positive models behaved better.[15] Modern children can be exposed to much more history, news and science than previous generations when information was only available from newspapers and books.
[edit] Television Schools
* Asian Academy Of Film & Television
* Asian School Of Media Studies
[edit] Environmental aspects
With high lead content in CRTs, and the rapid diffusion of new, flat-panel display technologies, some of which (LCDs) use lamps containing mercury, there is growing concern about electronic waste from discarded televisions. Related occupational health concerns exist, as well, for disassemblers removing copper wiring and other materials from CRTs. Further environmental concerns related to television design and use relate to the devices' increasing electrical energy requirements.[16]
[edit] References
1. ^ John Watkinson, Convergence in Broadcast and Communications Media: The Fundamentals of Audio, Video, Data, Focal Press, 2001, ISBN 0240515099
2. ^ HANNSwood 10 inch LCD Television, HANNspree
3. ^ Retro Thing: Video + TV.
4. ^ Jon Stewart of "The Daily Show" was mock-outraged at this, saying, "That's what we do!", and calling it a new form of television, "infoganda".
5. ^ "Watch TV anywhere on tiny set that fits on glasses", Reuters, May 22, 2007. Retrieved on 2007-08-31.
6. ^ Jhally, Sut (2000). "Advertising at the Edge of the Apocalypse". Critical Studies in Media Commercialism: 27–39. ISBN 0198742770. Retrieved on 2007-08-31.
7. ^ Pecora, Norma; John P. Murray, & Ellen A. Wartella (June, 2006). hildren and Television (TV): 50 Years of Research. Erlbaum Pres.
8. ^ Murray, John P. (February, 2006). "Children's Brain Activations While Viewing Televised Violence Revealed by fMRI". Media Psychology 8 (1): 25–37. DOI:10.1207/S1532785XMEP0801_3.
9. ^ Kubey, Robert & Mihaly Csikszentmihalyi (February 23, 2002), "Television Addiction Is No Mere Metaphor", Scientific American,
10. ^ Hancox, MD, Robert J.; Barry J. Milne, MSc; Richie Poulton, PhD (2005). "Association of Television Viewing During Childhood With Poor Educational Achievement". Pediatrics and Adolescent Medicine 159 (7): 614–618. Retrieved on 2007-06-18.
11. ^ Schooler, Deborah; Janna L. Kim, and Lynn Sorsoli (December 2006). "Setting Rules or Sitting Down: Parental Mediation of Television Consumption and Adolescent Self-Esteem, Body Image, and Sexuality". Sexuality Research and Social Policy: Journal of NSRC 3 (4): 49–62. DOI:10.1525. Retrieved on 2007-06-18.
12. ^ Hershberger, Angela. "The ``Evils" of Television: The Amount of Television Viewing and School Performance Levels". Indiana University South Bend. Retrieved on 2007-06-18.
13. ^ "Psychological Operations Field Manual No.33-1" published in August 1979 by Department of the Army Headquarters in Washington DC; and "Psychological Operations (PSYOP) Media Subcourse PO-0816" by The Army Institute for Professional Development, published in 1983
14. ^ Propaganda#Techniques of propaganda transmission
15. ^ Dimitri Christakis. "Smarter kids through television: debunking myths old and new", Seattle Times Newspaper, February 22, 2007. Retrieved on 2007-08-31.
16. ^ The Rise of the Machines: A Review of Energy Using Products in the Home from the 1970s to Today (PDF). Energy Saving Trust (July 3, 2006). Retrieved on 2007-08-31.
[edit] Further reading
Find more information on Television by searching Wikipedia's sister projects
Dictionary definitions from Wiktionary
Textbooks from Wikibooks
Quotations from Wikiquote
Source texts from Wikisource
Images and media from Commons
News stories from Wikinews
Learning resources from Wikiversity
* Pierre Bourdieu, On Television, The New Press, 2001.
* Brooks, Tim and March, Earle, The Complete Guide to Prime Time Network and Cable TV Shows, Ballantine, Eighth Edition, 2002.
* Jacques Derrida, Bernard Stiegler, Echographies of Television, Polity Press, 2002.
* Jerry Mander, Four Arguments for the Elimination of Television, Perennial, 1978.
* Jerry Mander, In the Absence of the Sacred, Sierra Club Books, 1992, ISBN 0-87156-509-9. Makes the case that television programming transmitted by communications satellites is destroying unique local cultures all over the world
* Neil Postman, Amusing Ourselves to Death: Public Discourse in the Age of Show Business. Penguin USA, 1985. ISBN 0-670-80454-1
* Beretta E. Smith-Shomade, Shaded Lives: African-American Women and Television, Rutgers University Press, 2002.
* Dr. Alan. Taylor,We, the media, Pedagogic Intrusions into US Film and Television News... ISBN 3631518528 Peter, Lang, Academic Book Publishers, 2005, pp. 418.
* David E. Fisher and Marshall J. Fisher, Tube: the Invention of Television, Counterpoint, Washington, D.C., USA, (1996) ISBN 1-887178-17-1
* Albert Abramson, The History of Television, 1942 to 2000, McFarland, Jefferson, NC, USA, and London (2003) ISBN 0-7864-1220-8
* Evan I. Schwartz, The Last Lone Inventor: A Tale of Genius, Deceit, and the Birth of Television
The Internet is a worldwide, publicly accessible series of interconnected computer networks that transmit data by packet switching using the standard Internet Protocol (IP). It is a "network of networks" that consists of millions of smaller domestic, academic, business, and government networks, which together carry various information and services, such as electronic mail, online chat, file transfer, and the interlinked Web pages and other documents of the World Wide Web.The Internet and the World Wide Web are not synonymous. The Internet is a collection of interconnected computer networks, linked by copper wires, fiber-optic cables, wireless connections, etc. In contrast, the Web is a collection of interconnected documents and other resources, linked by hyperlinks and URLs. The World Wide Web is one of the services accessible via the Internet, along with many others including e-mail, file sharing and others described below.
The Internet protocol suite is a collection of standards and protocols organized into layers so that each layer provides the foundation and the services required by the layer above. In this scheme, the Internet consists of the computers and networks that handle Internet Protocol (IP) data packets. Transmission Control Protocol (TCP) depends on IP and solves problems like data packets arriving out of order or not at all. Next comes Hypertext Transfer Protocol (HTTP), which is an application layer protocol. It runs on top of TCP/IP and provides user agents, such as web browsers, with access to the files, documents and other resources of the World Wide Web.
History
Main article: History of the Internet
Creation
Main article: ARPANET
The USSR's launch of Sputnik spurred the United States to create the Advanced Research Projects Agency, known as ARPA, in February 1958 to regain a technological lead.[1][2] ARPA created the Information Processing Technology Office (IPTO) to further the research of the Semi Automatic Ground Environment (SAGE) program, which had networked country-wide radar systems together for the first time. J. C. R. Licklider was selected to head the IPTO, and saw universal networking as a potential unifying human revolution.
Licklider moved from the Psycho-Acoustic Laboratory at Harvard University to MIT in 1950, after becoming interested in information technology. At MIT, he served on a committee that established Lincoln Laboratory and worked on the SAGE project. In 1957 he became a Vice President at BBN, where he bought the first production PDP-1 computer and conducted the first public demonstration of time-sharing.
At the IPTO, Licklider recruited Lawrence Roberts to head a project to implement a network, and Roberts based the technology on the work of Paul Baran[citation needed] who had written an exhaustive study for the U.S. Air Force that recommended packet switching (as opposed to circuit switching) to make a network highly robust and survivable. After much work, the first two nodes of what would become the ARPANET were interconnected between UCLA and SRI International in Menlo Park, California, on October 29, 1969. The ARPANET was one of the "eve" networks of today's Internet. Following on from the demonstration that packet switching worked on the ARPANET, the British Post Office, Telenet, DATAPAC and TRANSPAC collaborated to create the first international packet switched network service. In the UK, this was referred to as the International Packet Stream Service (IPSS), in 1978. The collection of X.25-based networks grew from Europe and the US to cover Canada, Hong Kong and Australia by 1981. The X.25 packet switching standard was developed in the CCITT (now called ITU-T) around 1976. There were independent of the TCP/IP protocols that arose from the experimental work of DARPA on the ARPANET, Packet Radio Net and Packet Satellite Net during the same time period. Vinton Cerf and Robert Kahn developed the first description of the TCP protocols during 1973 and published a paper on the subject in May 1974. Use of the term "Internet" to describe a single global TCP/IP network originated in December 1974 with the publication of RFC 674, the first full specification of TCP that was written by Vinton Cerf, Yogen Dalal and Carl Sunshine then at Stanford University. During the next nine years, work proceeded to refine the protocols and to implement them on a wide range of operating systems.
The first TCP/IP-wide area network was made operational by January 1, 1983 when all hosts on the ARPANET were switched over from the older NCP protocols to TCP/IP. In 1985, the United States' National Science Foundation (NSF) commissioned the construction of a university 56 kilobit/second network backbone using computers called "fuzzballs" by their inventor, David Mills. The following year, NSF sponsored the development of a higher speed 1.5 megabit/second backbone that become the NSFNet. A key decision to use the DARPA TCP/IP protocols was made by Dennis Jennings, then in charge of the Supercomputer program at NSF.
The opening of the network to commercial interests began in 1988. The US Federal Networking Council approved the interconnection of the NSFNET to the commercial MCI Mail system in that year and the link was made in the summer of 1989. Other commercial electronic email services were soon connected, including OnTyme, Telemail and Compuserve. In that same year, three commercial Internet Service Providers were created: UUNET, PSINET and CERFNET. Important, separate networks that offered gateways into, then later merged with the Internet include Usenet and BITNET. Various other commercial and educational networks, such as Telenet, Tymnet, Compuserve and JANET were interconnected with the growing Internet. Telenet (later called Sprintnet) was a large privately-funded national computer network with free dial-up access in cities throughout the U.S. that had been in operation since the 1970s. This network was eventually interconnected with the others in the 1980s as the TCP/IP protocol became increasingly popular. The ability of TCP/IP to work over virtually any pre-existing communication networks allowed for a great ease of growth although the rapid growth of the Internet was due primarily to the availability of commercial routers from companies such as Cisco Systems, Proteon and Juniper, the availability of commercial Ethernet equipment for local area networking and the widespread implementation of TCP/IP on the UNIX operating system.
Growth
The network gained a public face in the 1990s. On August 6, 1991, CERN, which straddles the border between France and Switzerland, publicized the new World Wide Web project, two years after British scientist Tim Berners-Lee had begun creating HTML, HTTP and the first few Web pages at CERN.
An early popular web browser was ViolaWWW based upon HyperCard. It was eventually replaced in popularity by the Mosaic web browser. In 1993 the National Center for Supercomputing Applications at the University of Illinois released version 1.0 of Mosaic, and by late 1994 there was growing public interest in the previously academic/technical Internet. By 1996 usage of the word "Internet" had become commonplace, and consequently, so had its misusage as a reference to the World Wide Web.
Meanwhile, over the course of the decade, the Internet successfully accommodated the majority of previously existing public computer networks (although some networks, such as FidoNet, have remained separate) During the 1990s, it was estimated that the Internet grew by 100% per year, with a brief period of explosive growth in 1996 and 1997.[3] This growth is often attributed to the lack of central administration, which allows organic growth of the network, as well as the non-proprietary open nature of the Internet protocols, which encourages vendor interoperability and prevents any one company from exerting too much control over the network. [citation needed]
Today's Internet
A rack of servers
A rack of servers
Aside from the complex physical connections that make up its infrastructure, the Internet is facilitated by bi- or multi-lateral commercial contracts (e.g., peering agreements), and by technical specifications or protocols that describe how to exchange data over the network. Indeed, the Internet is essentially defined by its interconnections and routing policies.
As of June 10, 2007, 1.133 billion people use the Internet according to Internet World Stats. Writing in the Harvard International Review, philosopher N.J.Slabbert, a writer on policy issues for the Washington DC-based Urban Land Institute, has asserted that the Internet is fast becoming a basic feature of global civilization, so that what has traditionally been called "civil society" is now becoming identical with information technology society as defined by Internet use. [4]
Internet protocols
For more details on this topic, see Internet Protocols.
In this context, there are three layers of protocols:
* At the lower level (OSI layer 3) is IP (Internet Protocol), which defines the datagrams or packets that carry blocks of data from one node to another. The vast majority of today's Internet uses version four of the IP protocol (i.e. IPv4), and although IPv6 is standardized, it exists only as "islands" of connectivity, and there are many ISPs without any IPv6 connectivity. [1]. ICMP (Internet Control Message Protocol) also exists at this level. ICMP is connectionless; it is used for control, signaling, and error reporting purposes.
* TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) exist at the next layer up (OSI layer 4); these are the protocols by which data is transmitted. TCP makes a virtual 'connection', which gives some level of guarantee of reliability. UDP is a best-effort, connectionless transport, in which data packets that are lost in transit will not be re-sent.
* The application protocols sit on top of TCP and UDP and occupy layers 5, 6, and 7 of the OSI model. These define the specific messages and data formats sent and understood by the applications running at each end of the communication. Examples of these protocols are HTTP, FTP, and SMTP.
Internet structure
There have been many analyses of the Internet and its structure. For example, it has been determined that the Internet IP routing structure and hypertext links of the World Wide Web are examples of scale-free networks.
Similar to the way the commercial Internet providers connect via Internet exchange points, research networks tend to interconnect into large subnetworks such as:
* GEANT
* GLORIAD
* The Internet2 Network (formally known as the Abilene Network)
* JANET (the UK's national research and education network)
These in turn are built around relatively smaller networks. See also the list of academic computer network organizations
In network diagrams, the Internet is often represented by a cloud symbol, into and out of which network communications can pass.
ICANN
ICANN headquarters in Marina Del Rey
ICANN headquarters in Marina Del Rey
For more details on this topic, see ICANN.
The Internet Corporation for Assigned Names and Numbers (ICANN) is the authority that coordinates the assignment of unique identifiers on the Internet, including domain names, Internet Protocol (IP) addresses, and protocol port and parameter numbers. A globally unified namespace (i.e., a system of names in which there is one and only one holder of each name) is essential for the Internet to function. ICANN is headquartered in Marina del Rey, California, but is overseen by an international board of directors drawn from across the Internet technical, business, academic, and non-commercial communities. The US government continues to have the primary role in approving changes to the root zone file that lies at the heart of the domain name system. Because the Internet is a distributed network comprising many voluntarily interconnected networks, the Internet, as such, has no governing body. ICANN's role in coordinating the assignment of unique identifiers distinguishes it as perhaps the only central coordinating body on the global Internet, but the scope of its authority extends only to the Internet's systems of domain names, IP addresses, and protocol port and parameter numbers.
On November 16, 2005, the World Summit on the Information Society, held in Tunis, established the Internet Governance Forum (IGF) to discuss Internet-related issues.
Language
For more details on this topic, see English on the Internet.
Further information: Unicode
The prevalent language for communication on the Internet is English. This may be a result of the Internet's origins, as well as English's role as the lingua franca. It may also be related to the poor capability of early computers, largely originating in the United States, to handle characters other than those in the English variant of the Latin alphabet.
After English (30% of Web visitors) the most-requested languages on the World Wide Web are Chinese 14%, Spanish 8%, Japanese 8%, German 5%, French 5%, Portuguese 3.5%, Korean 3%, Italian 3% and Arabic 2.5% (from Internet World Stats, updated January 11, 2007).
By continent, 36% of the world's Internet users are based in Asia, 29% in Europe, and 21% in North America ([2] updated January 11, 2007).
The Internet's technologies have developed enough in recent years, especially in the use of Unicode, that good facilities are available for development and communication in most widely used languages. However, some glitches such as mojibake (incorrect display of foreign language characters, also known as kryakozyabry) still remain.
Internet and the workplace
The Internet is allowing greater flexibility in working hours and location, especially with the spread of unmetered high-speed connections and Web applications.
The Internet Viewed on Mobile Devices
The Internet can now be accessed virtually anywhere by numerous means. Mobile phones, datacards, handheld game consoles and cellular routers allow users to connect to the Internet from anywhere there is a cellular network supporting that device's technology.
Common uses of the Internet
E-mail
For more details on this topic, see E-mail.
The concept of sending electronic text messages between parties in a way analogous to mailing letters or memos predates the creation of the Internet. Even today it can be important to distinguish between Internet and internal e-mail systems. Internet e-mail may travel and be stored unencrypted on many other networks and machines out of both the sender's and the recipient's control. During this time it is quite possible for the content to be read and even tampered with by third parties, if anyone considers it important enough. Purely internal or intranet mail systems, where the information never leaves the corporate or organization's network, are much more secure, although in any organization there will be IT and other personnel whose job may involve monitoring, and occasionally accessing, the email of other employees not addressed to them.
The World Wide Web
For more details on this topic, see World Wide Web.
Graphic representation of less than 0.0001% of the WWW, representing some of the hyperlinks
Graphic representation of less than 0.0001% of the WWW, representing some of the hyperlinks
Many people use the terms Internet and World Wide Web (or just the Web) interchangeably, but, as discussed above, the two terms are not synonymous.
The World Wide Web is a huge set of interlinked documents, images and other resources, linked by hyperlinks and URLs. These hyperlinks and URLs allow the web-servers and other machines that store originals, and cached copies, of these resources to deliver them as required using HTTP. HTTP is only one of the communication protocols used on the Internet.
Web services also use HTTP to allow software systems to communicate in order to share and exchange business logic and data.
Software products that can access the resources of the Web are correctly termed user agents. In normal use, Web browsers, such as Internet Explorer and Firefox access Web pages and allow users to navigate from one to another via hyperlinks. Web documents may contain almost any combination of computer data including photographs, graphics, sounds, text, video, multimedia and interactive content including games, office applications and scientific demonstrations.
Through keyword-driven Internet research using search engines, like Yahoo!, and Google, millions of people worldwide have easy, instant access to a vast and diverse amount of online information. Compared to encyclopedias and traditional libraries, the World Wide Web has enabled a sudden and extreme decentralization of information and data.
It is also easier using the Web than ever before for individuals and organisations to publish ideas and information to an extremely large audience. Anyone can find ways to publish a web page or build a website for very little initial cost. Publishing and maintaining large, professional websites full of attractive, diverse and up-to-date information is still a difficult and expensive proposition, however.
Many individuals and some companies and groups use "Web logs" or blogs, which are largely used as easily-updatable online diaries. Some commercial organizations encourage staff to fill them with advice on their areas of specialization in the hope that visitors will be impressed by the expert knowledge and free information, and be attracted to the corporation as a result. One example of this practice is Microsoft, whose product developers publish their personal blogs in order to pique the public's interest in their work.
Collections of personal Web pages published by large service providers remain popular, and have become increasingly sophisticated. Whereas operations such as Angelfire and GeoCities have existed since the early days of the Web, newer offerings from, for example, Facebook and MySpace currently have large followings. These operations often brand themselves as social network services rather than simply as Web page hosts.
Advertising on popular Web pages can be lucrative, and e-commerce or the sale of products and services directly via the Web continues to grow.
In the early days, Web pages were usually created as sets of complete and isolated HTML text files stored on a Web server. More recently, Web sites are more often created using content management system (CMS) software with, initially, very little content. Users of the CMS, who may be paid staff, members of a club or other organisation, or even members of the public, fill the CMS database with content using editing pages designed for that purpose, while casual visitors view and read this content in its final HTML form. There may or may not be editorial, approval and security systems built into the process of taking newly entered content and making it available to the target visitors.
Remote access
Further information: Remote access
The Internet allows computer users to connect to other computers and information stores easily, wherever they may be across the world. They may do this with or without the use of security, authentication and encryption technologies, depending on the requirements.
This is encouraging new ways of working from home, collaboration and information sharing in many industries. An accountant sitting at home can audit the books of a company based in another country, on a server situated in a third country that is remotely maintained by IT specialists in a fourth. These accounts could have been created by home-working book-keepers, in other remote locations, based on information e-mailed to them from offices all over the world. Some of these things were possible before the widespread use of the Internet, but the cost of private, leased lines would have made many of them infeasible in practice.
An office worker away from his desk, perhaps the other side of the world on a business trip or a holiday, can open a remote desktop session into their normal office PC using a secure Virtual Private Network (VPN) connection via the Internet. This gives the worker complete access to all of their normal files and data, including e-mail and other applications, while away from the office.
This concept is also referred to by some network security people as the Virtual Private Nightmare, because it extends the secure perimeter of a corporate network into its employees' homes; this has been the source of some notable security breaches, but also provides security for the workers.
Collaboration
See also: Collaborative software
The low cost and nearly instantaneous sharing of ideas, knowledge, and skills has made collaborative work dramatically easier. Not only can a group cheaply communicate and test, but the wide reach of the Internet allows such groups to easily form in the first place, even among niche interests. An example of this is the free software movement in software development which produced GNU and Linux from scratch and has taken over development of Mozilla and OpenOffice.org (formerly known as Netscape Communicator and StarOffice).
Internet 'chat', whether in the form of IRC 'chat rooms' or channels, or via instant messaging systems allow colleagues to stay in touch in a very convenient way when working at their computers during the day. Messages can be sent and viewed even more quickly and conveniently than via e-mail. Extension to these systems may allow files to be exchanged, 'whiteboard' drawings to be shared as well as voice and video contact between team members.
Version control systems allow collaborating teams to work on shared sets of documents without either accidentally overwriting each other's work or having members wait until they get 'sent' documents to be able to add their thoughts and changes.
File sharing
For more details on this topic, see File sharing.
A computer file can be e-mailed to customers, colleagues and friends as an attachment. It can be uploaded to a Web site or FTP server for easy download by others. It can be put into a "shared location" or onto a file server for instant use by colleagues. The load of bulk downloads to many users can be eased by the use of "mirror" servers or peer-to-peer networks.
In any of these cases, access to the file may be controlled by user authentication; the transit of the file over the Internet may be obscured by encryption and money may change hands before or after access to the file is given. The price can be paid by the remote charging of funds from, for example a credit card whose details are also passed—hopefully fully encrypted—across the Internet. The origin and authenticity of the file received may be checked by digital signatures or by MD5 or other message digests.
These simple features of the Internet, over a world-wide basis, are changing the basis for the production, sale, and distribution of anything that can be reduced to a computer file for transmission. This includes all manner of print publications, software products, news, music, film, video, photography, graphics and the other arts. This in turn has caused seismic shifts in each of the existing industries that previously controlled the production and distribution of these products in that country.
Internet collaboration technology enables business and project teams to share documents, calendars and other information. Such collaboration occurs in a wide variety of areas including scientific research, software development, conference planning, political activism and creative writing.
Streaming media
Many existing radio and television broadcasters provide Internet 'feeds' of their live audio and video streams (for example, the BBC and Rush Limbaugh). They may also allow time-shift viewing or listening such as Preview, Classic Clips and Listen Again features. These providers have been joined by a range of pure Internet 'broadcasters' who never had on-air licenses. This means that an Internet-connected device, such as a computer or something more specific, can be used to access on-line media in much the same way as was previously possible only with a television or radio receiver. The range of material is much wider, from pornography to highly specialized technical Web-casts. Podcasting is a variation on this theme, where—usually audio—material is first downloaded in full and then may be played back on a computer or shifted to a digital audio player to be listened to on the move. These techniques using simple equipment allow anybody, with little censorship or licensing control, to broadcast audio-visual material on a worldwide basis.
Webcams can be seen as an even lower-budget extension of this phenomenon. While some webcams can give full frame rate video, the picture is usually either small or updates slowly. Internet users can watch animals around an African waterhole, ships in the Panama Canal, the traffic at a local roundabout or their own premises, live and in real time. Video chat rooms, video conferencing, and remote controllable webcams are also popular. Many uses can be found for personal webcams in and around the home, with and without two-way sound.
Voice telephony (VoIP)
For more details on this topic, see VoIP.
VoIP stands for Voice over IP, where IP refers to the Internet Protocol that underlies all Internet communication. This phenomenon began as an optional two-way voice extension to some of the Instant Messaging systems that took off around the year 2000. In recent years many VoIP systems have become as easy to use and as convenient as a normal telephone. The benefit is that, as the Internet carries the actual voice traffic, VoIP can be free or cost much less than a normal telephone call, especially over long distances and especially for those with always-on Internet connections such as cable or ADSL.
Thus VoIP is maturing into a viable alternative to traditional telephones. Interoperability between different providers has improved and the ability to call or receive a call from a traditional telephone is available. Simple inexpensive VoIP modems are now available that eliminate the need for a PC.
Voice quality can still vary from call to call but is often equal to and can even exceed that of traditional calls.
Remaining problems for VoIP include emergency telephone number dialling and reliability. Currently a few VoIP providers provide an emergency service but it is not universally available. Traditional phones are line powered and operate during a power failure, VoIP does not do so without a backup power source for the electronics.
Most VoIP providers offer unlimited national calling but the direction in VoIP is clearly toward global coverage with unlimited minutes for a low monthly fee.
VoIP has also become increasingly popular within the gaming world, as a form of communication between players. Popular gaming VoIP clients include Ventrilo and Teamspeak, and there are others available also.
Censorship
For more details on this topic, see Internet censorship.
Some governments, such as those of Cuba, Iran, North Korea, the People's Republic of China and Saudi Arabia, restrict what people in their countries can access on the Internet, especially political and religious content. This is accomplished through software that filters domains and content so that they may not be easily accessed or obtained without elaborate circumvention.
In Norway, Finland and Sweden, major Internet service providers have voluntarily (possibly to avoid such an arrangement being turned into law) agreed to restrict access to sites listed by police. While this list of forbidden URLs is only supposed to contain addresses of known child pornography sites, the content of the list is secret.[citation needed]
Many countries have enacted laws making the possession or distribution of certain material, such as child pornography, illegal, but do not use filtering software.
There are many free and commercially available software programs with which a user can choose to block offensive Web sites on individual computers or networks, such as to limit a child's access to pornography or violence. See Content-control software.
Internet access
For more details on this topic, see Internet access.
Wikibooks
Wikibooks has more about this subject:
Online linux connect
Common methods of home access include dial-up, landline broadband (over coaxial cable, fiber optic or copper wires), Wi-Fi, satellite and technology 3G cell phones.
Public places to use the Internet include libraries and Internet cafes, where computers with Internet connections are available. There are also Internet access points in many public places such as airport halls and coffee shops, in some cases just for brief use while standing. Various terms are used, such as "public Internet kiosk", "public access terminal", and "Web payphone". Many hotels now also have public terminals, though these are usually fee-based.
Wi-Fi provides wireless access to computer networks, and therefore can do so to the Internet itself. Hotspots providing such access include Wi-Fi-cafes, where a would-be user needs to bring their own wireless-enabled devices such as a laptop or PDA. These services may be free to all, free to customers only, or fee-based. A hotspot need not be limited to a confined location. The whole campus or park, or even the entire city can be enabled. Grassroots efforts have led to wireless community networks. Commercial WiFi services covering large city areas are in place in London, Vienna, Toronto, San Francisco, Philadelphia, Chicago and Pittsburgh. The Internet can then be accessed from such places as a park bench.[5]
Apart from Wi-Fi, there have been experiments with proprietary mobile wireless networks like Ricochet, various high-speed data services over cellular phone networks, and fixed wireless services.
High-end mobile phones such as smartphones generally come with Internet access through the phone network. Web browsers such as Opera are available on these advanced handsets, which can also run a wide variety of other Internet software. More mobile phones have Internet access than PCs, though this is not as widely used. An Internet access provider and protocol matrix differentiates the methods used to get online.
Leisure
The Internet has been a major source of leisure since before the World Wide Web, with entertaining social experiments such as MUDs and MOOs being conducted on university servers, and humor-related Usenet groups receiving much of the main traffic. Today, many Internet forums have sections devoted to games and funny videos; short cartoons in the form of Flash movies are also popular. Over 6 million people use blogs or message boards as a means of communication and for the sharing of ideas.
The pornography and gambling industries have both taken full advantage of the World Wide Web, and often provide a significant source of advertising revenue for other Web sites. Although many governments have attempted to put restrictions on both industries' use of the Internet, this has generally failed to stop their widespread popularity. A song in the Broadway musical show Avenue Q is titled "The Internet is for Porn" and refers to the popularity of this aspect of the Internet.
One main area of leisure on the Internet is multiplayer gaming. This form of leisure creates communities, bringing people of all ages and origins to enjoy the fast-paced world of multiplayer games. These range from MMORPG to first-person shooters, from role-playing games to online gambling. This has revolutionized the way many people interact and spend their free time on the Internet.
While online gaming has been around since the 1970s, modern modes of online gaming began with services such as GameSpy and MPlayer, which players of games would typically subscribe to. Non-subscribers were limited to certain types of gameplay or certain games.
Many use the Internet to access and download music, movies and other works for their enjoyment and relaxation. As discussed above, there are paid and unpaid sources for all of these, using centralized servers and distributed peer-to-peer technologies. Discretion is needed as some of these sources take more care over the original artists' rights and over copyright laws than others.
Many use the World Wide Web to access news, weather and sports reports, to plan and book holidays and to find out more about their random ideas and casual interests.
People use chat, messaging and email to make and stay in touch with friends worldwide, sometimes in the same way as some previously had pen pals. Social networking Web sites like Friends Reunited and many others like them also put and keep people in contact for their enjoyment.
The Internet has seen a growing amount of Internet operating systems, where users can access their files, folders, and settings via the Internet. An example of an opensource webOS is Eyeos.
Cyberslacking has become a serious drain on corporate resources; the average UK employee spends 57 minutes a day surfing the Web at work, according to a study by Peninsula Business Services [3].
Complex architecture
Many computer scientists see the Internet as a "prime example of a large-scale, highly engineered, yet highly complex system".[6] The Internet is extremely heterogeneous. (For instance, data transfer rates and physical characteristics of connections vary widely.) The Internet exhibits "emergent phenomena" that depend on its large-scale organization. For example, data transfer rates exhibit temporal self-similarity. Further adding to the complexity of the Internet is the ability of more than one computer to use the Internet through only one node, thus creating the possibility for a very deep and hierarchal based sub-network that can theoretically be extended infinitely (disregarding the programmatic limitations of the IPv4 protocol). However, since principles of this architecture date back to the 1960s, it might not be a solution best suited to modern needs, and thus the possibility of developing alternative structures is currently being looked into. Thanks to studies done in the Hebrew University in Jerusalem, it has been shown that the internet is in the shape of a sphere or medusa jellyfish. There are 3 sections of this sphere. The core of the internet is made up of around a 100 of the most tightly connected subnetworks, such as Google. [7]
Marketing
The Internet has also become a large market for companies; some of the biggest companies today have grown by taking advantage of the efficient nature of low-cost advertising and commerce through the Internet; also known as e-commerce. It is the fastest way to spread information to a vast amount of people simultaneously. The Internet has also subsequently revolutionized shopping—for example; a person can order a CD online and receive it in the mail within a couple of days, or download it directly in some cases. The Internet has also greatly facilitated personalized marketing which allows a company to market a product to a specific person or a specific group of people more so than any other advertising medium.
Examples of personalized marketing include online communities such as MySpace, Friendster, Orkut, Facebook and others which thousands of Internet users join to advertise themselves and make friends online. Many of these users are young teens and adolescents ranging from 13 to 25 years old. In turn, when they advertise themselves they advertise interests and hobbies, which online marketing companies can use as information as to what those users will purchase online, and advertise their own companies' products to those users.
Further information: Disintermediation#Impact of Internet-related disintermediation upon various industries and Travel agency#The Internet threat
The name Internet
For more details on this topic, see Internet capitalization conventions.
Look up Internet, internet in Wiktionary, the free dictionary.
Internet is traditionally written with a capital first letter, as it is a proper noun. The Internet Society, the Internet Engineering Task Force, the Internet Corporation for Assigned Names and Numbers, the World Wide Web Consortium, and several other Internet-related organizations use this convention in their publications.
Many newspapers, newswires, periodicals, and technical journals capitalize the term (Internet). Examples include The New York Times, the Associated Press, Time, The Times of India, Hindustan Times, and Communications of the ACM.
Others assert that the first letter should be in lower case (internet), and that the specific article “the” is sufficient to distinguish “the internet” from other internets. A significant number of publications use this form, including The Economist, the Canadian Broadcasting Corporation, the Financial Times, The Guardian, The Times, and The Sydney Morning Herald. As of 2005, many publications using internet appear to be located outside of North America—although one U.S. news source, Wired News, has adopted the lower-case spelling.
Historically, Internet and internet have had different meanings, with internet meaning “an interconnected set of distinct networks,” and Internet referring to the world-wide, publicly-available IP internet. Under this distinction, "the Internet" is the familiar network via which websites exist, however "an internet" can exist between any two remote locations.[8] Any group of distinct networks connected together is an internet; each of these networks may or may not be part of the Internet. The distinction was evident in many RFCs, books, and articles from the 1980s and early 1990s (some of which, such as RFC 1918, refer to "internets" in the plural), but has recently fallen into disuse.[citation needed] Instead, the term intranet is generally used for private networks. See also: extranet.
Some people use the lower-case term as a medium (like radio or newspaper, e.g. I've found it on the internet), and first letter capitalized as the global network.
See also
Find more information on Internet by searching Wikipedia's sister projects
Dictionary definitions from Wiktionary
Textbooks from Wikibooks
Quotations from Wikiquote
Source texts from Wikisource
Images and media from Commons
News stories from Wikinews
Learning resources from Wikiversity
Main articles: List of basic internet topics and List of Internet topics
Major aspects and issues
* Internet democracy
* History of the Internet
* Net neutrality
* Privacy on the Internet
Functions
* E-mail
* File-sharing
* Instant messaging
* Internet fax
* World Wide Web
* Voice over IP
Underlying infrastructure
* Internet Protocol (IP)
* Internet Service Provider (ISP)
* Series of tubes
Regulatory bodies
* Internet Assigned Numbers Authority (IANA)
* Internet Corporation for Assigned Names and Numbers (ICANN)
Notes
1. ^ ARPA/DARPA. Defense Advanced Research Projects Agency. Retrieved on 2007-05-21.
2. ^ DARPA Over the Years. Defense Advanced Research Projects Agency. Retrieved on 2007-05-21.
3. ^ Coffman, K. G; Odlyzko, A. M. (1998-10-02). "The size and growth rate of the Internet". AT&T Labs. Retrieved on 2007-05-21.
4. ^ Slabbert,N.J. The Technologies of Peace, Harvard International Review, June 2006.
5. ^ "Toronto Hydro to Install Wireless Network in Downtown Toronto". Bloomberg.com. Retrieved 19-Mar-2006.
6. ^ Walter Willinger, Ramesh Govindan, Sugih Jamin, Vern Paxson, and Scott Shenker (2002). Scaling phenomena in the Internet. In Proceedings of the National Academy of Sciences, 99, suppl. 1, 2573–2580.
7. ^ "Internet Makeover? Some argue it's time". The Seattle Times, April 16, 2007.
8. ^ What is the Internet?
References
* Media Freedom Internet Cookbook by the OSCE Representative on Freedom of the Media Vienna, 2004
* Living Internet—Internet history and related information, including information from many creators of the Internet
* First Monday peer-reviewed journal on the Internet
* How Much Does The Internet Weigh? by Stephen Cass, Discover 2007
Rehmeyer, Julie J. 2007. Mapping a medusa: The Internet spreads its tentacles. Science News 171(June 23):387-388. Available at http://www.sciencenews.org/articles/20070623/fob2.asp . Sohn, Emily. 2006. Internet generation. Science News for Kids (Oct. 25). Available at http://www.sciencenewsforkids.org/articles/20061025/Feature1.asp .