Television, sometimes shortened to TV, is a telecommunication
medium
Medium may refer to:
Science and technology
Aviation
* Medium bomber, a class of war plane
* Tecma Medium, a French hang glider design
Communication
* Media (communication), tools used to store and deliver information or data
* Medium ...
for
transmitting moving images and sound. The term can refer to a
television set
A television set or television receiver, more commonly called the television, TV, TV set, telly, tele, or tube, is a device that combines a tuner, display, and loudspeakers, for the purpose of viewing and hearing television broadcasts, or using ...
, or the medium of
television transmission. Television is a
mass medium
Mass media refers to a diverse array of media technologies that reach a large audience via mass communication. The technologies through which this communication takes place include a variety of outlets.
Broadcast media transmit information ...
for advertising, entertainment, news, and sports.
Television became available in crude experimental forms in the late 1920s, but only after several years of further development was the new technology marketed to consumers. After
World War II
World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...
, an improved form of black-and-white television broadcasting became popular in the United Kingdom and the United States, and television sets became commonplace in homes, businesses, and institutions. During the 1950s, television was the primary medium for influencing
public opinion
Public opinion is the collective opinion on a specific topic or voting intention relevant to a society. It is the people's views on matters affecting them.
Etymology
The term "public opinion" was derived from the French ', which was first use ...
.
[Diggs-Brown, Barbara (2011]
''Strategic Public Relations: Audience Focused Practice''
p. 48 In the mid-1960s, color broadcasting was introduced in the U.S. and most other developed countries.
The availability of various types of archival storage media such as
Betamax
Betamax (also known as Beta, as in its logo) is a consumer-level analog recording and cassette format of magnetic tape for video, commonly known as a video cassette recorder. It was developed by Sony and was released in Japan on May 10, 1975, ...
and
VHS tapes,
LaserDisc
The LaserDisc (LD) is a home video format and the first commercial optical disc storage medium, initially licensed, sold and marketed as MCA DiscoVision (also known simply as "DiscoVision") in the United States in 1978. Its diameter typical ...
s, high-capacity
hard disk drives
A hard disk drive (HDD), hard disk, hard drive, or fixed disk is an electro-mechanical data storage device that stores and retrieves digital data using magnetic storage with one or more rigid rapidly rotating platters coated with magn ...
,
CDs,
DVDs,
flash drives
A flash drive is a portable computer drive that uses flash memory. Flash drives are the larger memory modules consisting of a number of flash chips. A flash chip is used to read the contents of a single cell, but it can write entire block of cell ...
, high-definition
HD DVD
HD DVD (short for High Definition Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video. Supported principally by Toshiba, HD DVD was envisioned to be the successor to the ...
s and
Blu-ray Disc
The Blu-ray Disc (BD), often known simply as Blu-ray, is a digital optical disc data storage format. It was invented and developed in 2005 and released on June 20, 2006 worldwide. It is designed to supersede the DVD format, and capable of sto ...
s, and cloud
digital video recorders
A digital video recorder (DVR) is an electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device. The term includes set-top boxes with direct to d ...
has enabled viewers to watch pre-recorded material—such as movies—at home on their own time schedule. For many reasons, especially the convenience of remote retrieval, the storage of television and video programming now also occurs on
the cloud (such as the video-on-demand service by
Netflix
Netflix, Inc. is an American subscription video on-demand over-the-top streaming service and production company based in Los Gatos, California. Founded in 1997 by Reed Hastings and Marc Randolph in Scotts Valley, California, it offers a ...
). At the end of the first decade of the 2000s,
digital television
Digital television (DTV) is the transmission of television signals using digital encoding, in contrast to the earlier analog television technology which used analog signals. At the time of its development it was considered an innovative adva ...
transmissions greatly increased in popularity. Another development was the move from
standard-definition television
Standard-definition television (SDTV, SD, often shortened to standard definition) is a television system which uses a resolution that is not considered to be either high or enhanced definition. "Standard" refers to it being the prevailing sp ...
(SDTV) (
576i
576i is a standard-definition digital video mode, originally used for digitizing analog television in most countries of the world where the utility frequency for electric power distribution is 50 Hz. Because of its close association wit ...
, with 576
interlaced
Interlaced video (also known as interlaced scan) is a technique for doubling the perceived frame rate of a video display without consuming extra bandwidth. The interlaced signal contains two fields of a video frame captured consecutively. This ...
lines of resolution and
480i
480i is the video mode used for standard-definition digital television in the Caribbean, Japan, South Korea, Taiwan, Philippines, Laos, Western Sahara, and most of the Americas (with the exception of Argentina, Paraguay, and Uruguay). T ...
) to
high-definition television
High-definition television (HD or HDTV) describes a television system which provides a substantially higher image resolution than the previous generation of technologies. The term has been used since 1936; in more recent times, it refers to the g ...
(HDTV), which provides a
resolution that is substantially higher. HDTV may be transmitted in different formats:
1080p
1080p (1920×1080 progressively displayed pixels; also known as Full HD or FHD, and BT.709) is a set of HDTV high-definition video modes characterized by 1,920 pixels displayed across the screen horizontally and 1,080 pixels down the screen ve ...
,
1080i
1080i (also known as Full HD or BT.709) is a combination of frame resolution and scan type. 1080i is used in high-definition television (HDTV) and high-definition video. The number "1080" refers to the number of horizontal lines on the scree ...
and
720p
720p (1280×720 px; also called HD ready, standard HD or just HD) is a progressive HDTV signal format with 720 horizontal lines/1280 columns and an aspect ratio (AR) of 16:9, normally known as widescreen HDTV (1.78:1). All major HDTV broadcas ...
. Since 2010, with the invention of
smart television
A smart TV, also known as a connected TV (CTV), is a traditional television set with integrated Internet and interactive Web 2.0 features, which allows users to stream music and videos, browse the internet, and view photos. Smart TVs are a tec ...
,
Internet television
Streaming television is the digital distribution of television content, such as TV shows, as streaming media delivered over the Internet. Streaming television stands in contrast to dedicated terrestrial television delivered by over-the-air ...
has increased the availability of television programs and movies via the Internet through
streaming video
Video on demand (VOD) is a media distribution system that allows users to access videos without a traditional video playback device and the constraints of a typical static broadcasting schedule. In the 20th century, broadcasting in the form of ...
services such as Netflix,
Amazon Prime Video
Amazon Prime Video, also known simply as Prime Video, is an American subscription video on-demand over-the-top streaming and rental service of Amazon offered as a standalone service or as part of Amazon's Prime subscription. The service pr ...
,
iPlayer
BBC iPlayer (stylised as iPLAYER or BBC iPLAYER) is a video on demand service from the BBC. The service is available on a wide range of devices, including mobile phones and tablets, personal computers and smart televisions. iPlayer services del ...
and
Hulu
Hulu () is an American subscription streaming service majority-owned by The Walt Disney Company, with Comcast's NBCUniversal holding a minority stake. It was launched on October 29, 2007 and it offers a library of films and television series ...
.
In 2013, 79% of the world's
households
A household consists of two or more persons who live in the same dwelling. It may be of a single family or another type of person group. The household is the basic unit of analysis in many social, microeconomic and government models, and is im ...
owned a television set. The replacement of earlier
cathode-ray tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a Phosphorescence, phosphorescent screen. The images may represent electrical waveforms (osci ...
(CRT) screen displays with compact, energy-efficient, flat-panel alternative technologies such as
LCDs (both
fluorescent-backlit and
LED),
OLED
An organic light-emitting diode (OLED or organic LED), also known as organic electroluminescent (organic EL) diode, is a light-emitting diode (LED) in which the emissive electroluminescent layer is a film of organic compound that emits light i ...
displays, and
plasma display
A plasma display panel (PDP) is a type of flat panel display that uses small cells containing plasma: ionized gas that responds to electric fields. Plasma televisions were the first large (over 32 inches diagonal) flat panel displays to be rele ...
s was a hardware revolution that began with computer monitors in the late 1990s. Most television sets sold in the 2000s were flat-panel, mainly LEDs. Major manufacturers announced the discontinuation of CRT,
Digital Light Processing
Digital Light Processing (DLP) is a set of chipsets based on optical micro-electro-mechanical technology that uses a digital micromirror device. It was originally developed in 1987 by Larry Hornbeck of Texas Instruments. While the DLP imagin ...
(DLP), plasma, and even fluorescent-backlit LCDs by the mid-2010s.
In the near future, LEDs are expected to be gradually replaced by OLEDs.
Also, major manufacturers have announced that they will increasingly produce smart TVs in the mid-2010s.
Smart TVs with integrated Internet and
Web 2.0 functions became the dominant form of television by the late 2010s.
Television signals were initially distributed only as terrestrial television using high-powered
radio-frequency television transmitter
A television transmitter is a transmitter that is used for terrestrial (over-the-air) television broadcasting. It is an electronic device that radiates radio waves that carry a video signal representing moving images, along with a synchronized ...
s to
broadcast
Broadcasting is the distribution of audio or video content to a dispersed audience via any electronic mass communications medium, but typically one using the electromagnetic spectrum (radio waves), in a one-to-many model. Broadcasting began wi ...
the signal to individual television receivers. Alternatively television signals are distributed by
coaxial cable or optical fiber,
satellite
A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioiso ...
systems and, since the 2000s via the Internet. Until the early 2000s, these were transmitted as
analog signals, but a
transition to digital television was expected to be completed worldwide by the late 2010s. A standard television set consists of multiple internal
electronic circuit
An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow. It is a type of electric ...
s, including a tuner for
receiving and decoding broadcast signals. A visual
display device
A display device is an output device for presentation of information in visual or tactile form (the latter used for example in tactile electronic displays for blind people). When the input information that is supplied has an electrical signal the ...
which lacks a
tuner is correctly called a
video monitor rather than a television.
Etymology
The word ''television'' comes . The first documented usage of the term dates back to 1900, when the Russian scientist
Constantin Perskyi
Constantin Dmitrievich Perskyi (Константин Дмитриевич Перский) (2 June 18545 April 1906) was a Russian scientist who is credited with coining the word television (''télévision'') in a paper that he presented in French ...
used it in a paper that he presented in French at the first International Congress of Electricity, which ran from 18 to 25 August 1900 during the
International World Fair in Paris.
The
anglicised
Anglicisation is the process by which a place or person becomes influenced by English culture or British culture, or a process of cultural and/or linguistic change in which something non-English becomes English. It can also refer to the influen ...
version of the term is first attested in 1907, when it was still "...a theoretical system to transmit moving images over
telegraph
Telegraphy is the long-distance transmission of messages where the sender uses symbolic codes, known to the recipient, rather than a physical exchange of an object bearing the message. Thus flag semaphore is a method of telegraphy, whereas ...
or
telephone wires".
It was "...formed in English or borrowed from French ."
In the 19th century and early 20th century, other "...proposals for the name of a then-hypothetical technology for sending pictures over distance were telephote (1880) and televista (1904)."
The abbreviation ''TV'' is from 1948. The use of the term to mean "a
television set
A television set or television receiver, more commonly called the television, TV, TV set, telly, tele, or tube, is a device that combines a tuner, display, and loudspeakers, for the purpose of viewing and hearing television broadcasts, or using ...
" dates from 1941.
The use of the term to mean "television as a medium" dates from 1927.
The slang term ''telly'' is more common in the UK. The slang term "the tube" or the "boob tube" derives from the bulky
cathode-ray tube
A cathode-ray tube (CRT) is a vacuum tube containing one or more electron guns, which emit electron beams that are manipulated to display images on a Phosphorescence, phosphorescent screen. The images may represent electrical waveforms (osci ...
used on most TVs until the advent of
flat-screen TVs. Another slang term for the TV is "idiot box".
Also, in the 1940s and throughout the 1950s, during the early rapid growth of television programming and television set ownership in the United States, another slang term became widely used in that period and continues to be used today to distinguish productions originally created for broadcast on television from films developed for presentation in movie theaters.
[Johnson, Richard (2018)]
“Big movie stars are not making the cut on the small screen”
p. 6, '' The New York Post'', 11 October 2018. Retrieved 24 November 2018. The "small screen", as both a compound adjective and noun, became specific references to television, while the "
big screen
A feature film or feature-length film is a narrative film (motion picture or "movie") with a running time long enough to be considered the principal or sole presentation in a commercial entertainment program. The term ''feature film'' originall ...
" was used to identify productions made for theatrical release.
History
Mechanical
Facsimile transmission systems for still photographs pioneered methods of mechanical scanning of images in the early 19th century.
Alexander Bain introduced the facsimile machine between 1843 and 1846.
Frederick Bakewell
Frederick Collier Bakewell (29 September 1800 – 26 September 1869) was an English physicist who improved on the concept of the facsimile machine introduced by Alexander Bain in 1842 and demonstrated a working laboratory version at the 1 ...
demonstrated a working laboratory version in 1851.
Willoughby Smith discovered the
photoconductivity
Photoconductivity is an optical and electrical phenomenon in which a material becomes more electrically conductive due to the absorption of electromagnetic radiation such as visible light, ultraviolet light, infrared light, or gamma radiation ...
of the element
selenium
Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, ...
in 1873. As a 23-year-old German university student,
Paul Julius Gottlieb Nipkow proposed and patented the
Nipkow disk in 1884. This was a spinning disk with a spiral pattern of holes in it, so each hole scanned a line of the image. Although he never built a working model of the system, variations of Nipkow's spinning-disk "
image rasterizer" became exceedingly common.
Constantin Perskyi
Constantin Dmitrievich Perskyi (Константин Дмитриевич Перский) (2 June 18545 April 1906) was a Russian scientist who is credited with coining the word television (''télévision'') in a paper that he presented in French ...
had coined the word ''television'' in a paper read to the International Electricity Congress at the
International World Fair in Paris on 24 August 1900. Perskyi's paper reviewed the existing electromechanical technologies, mentioning the work of Nipkow and others. However, it was not until 1907 that developments in amplification tube technology by
Lee de Forest
Lee de Forest (August 26, 1873 – June 30, 1961) was an American inventor and a fundamentally important early pioneer in electronics. He invented the first electronic device for controlling current flow; the three-element " Audion" triode v ...
and
Arthur Korn
Arthur Korn (20 May 1870 – 21 December/22 December 1945) was a German physicist, mathematician and inventor. He was involved in the development of the fax machine, specifically the transmission of photographs or telephotography, known as the ...
, among others, made the design practical.
["Sending Photographs by Telegraph"](_blank)
''The New York Times'', Sunday Magazine, 20 September 1907, p. 7.
The first demonstration of the live transmission of images was by Georges Rignoux and A. Fournier in Paris in 1909. A matrix of 64
selenium
Selenium is a chemical element with the symbol Se and atomic number 34. It is a nonmetal (more rarely considered a metalloid) with properties that are intermediate between the elements above and below in the periodic table, sulfur and tellurium, ...
cells, individually wired to a mechanical
commutator
In mathematics, the commutator gives an indication of the extent to which a certain binary operation fails to be commutative. There are different definitions used in group theory and ring theory.
Group theory
The commutator of two elements, ...
, served as an electronic
retina
The retina (from la, rete "net") is the innermost, light-sensitive layer of tissue of the eye of most vertebrates and some molluscs. The optics of the eye create a focused two-dimensional image of the visual world on the retina, which the ...
. In the receiver, a type of
Kerr cell
The Kerr effect, also called the quadratic electro-optic (QEO) effect, is a change in the refractive index of a material in response to an applied electric field. The Kerr effect is distinct from the Pockels effect in that the induced index chang ...
modulated the light and a series of differently angled mirrors attached to the edge of a rotating disc scanned the modulated beam onto the display screen. A separate circuit regulated synchronization. The 8x8
pixel
In digital imaging, a pixel (abbreviated px), pel, or picture element is the smallest addressable element in a raster image, or the smallest point in an all points addressable display device.
In most digital display devices, pixels are the ...
resolution in this proof-of-concept demonstration was just sufficient to clearly transmit individual letters of the alphabet. An updated image was transmitted "several times" each second.
In 1911,
Boris Rosing
Boris Lvovich Rosing (russian: Борис Львович Розинг; 23 April 1869 (old style, 5 May 1869, new style). – 20 April 1933) was a Russian scientist and inventor in the field of television.
Biography
Boris Rosing was born in Sa ...
and his student
Vladimir Zworykin
Vladimir Kosma Zworykin; or with the patronymic as ''Kosmich''; or russian: Кузьмич, translit=Kuz'mich, label=none. Zworykin anglicized his name to ''Vladimir Kosma Zworykin'', replacing the patronymic with the name ''Kosma'' as a middle ...
created a system that used a mechanical mirror-drum scanner to transmit, in Zworykin's words, "very crude images" over wires to the "
Braun
Braun is a common surname, originating from the German word for the color brown. The name is the 22nd most common family name in Germany. Many German emigrants to the United Stat