
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 of ...
for
transmitting
In electronics and telecommunications, a radio transmitter or just transmitter is an electronic device which produces radio waves with an antenna. The transmitter itself generates a radio frequency alternating current, which is applied to th ...
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 e ...
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, 197 ...
and
VHS tapes,
LaserDiscs, 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 magnet ...
,
CDs
The compact disc (CD) is a digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then released in Octo ...
,
DVD
The DVD (common abbreviation for Digital Video Disc or Digital Versatile Disc) is a digital optical disc data storage format. It was invented and developed in 1995 and first released on November 1, 1996, in Japan. The medium can store any kin ...
s,
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 ...
s and
Blu-ray Discs, 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 advanc ...
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, 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. Thi ...
lines of resolution and
480i) 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 ...
(HDTV), which provides a
resolution
Resolution(s) may refer to:
Common meanings
* Resolution (debate), the statement which is debated in policy debate
* Resolution (law), a written motion adopted by a deliberative body
* New Year's resolution, a commitment that an individual ma ...
that is substantially higher. HDTV may be transmitted in different formats:
1080p,
1080i 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 te ...
,
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-ai ...
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 p ...
,
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 seri ...
.
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 impo ...
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 phosphorescent screen. The images may represent electrical waveforms ( oscilloscope), pi ...
(CRT) screen displays with compact, energy-efficient, flat-panel alternative technologies such as
LCDs (both
fluorescent-backlit and
LED
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (cor ...
),
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 ...
displays, and
plasma display
A plasma display panel (PDP) is a type of flat panel display that uses small cells containing Plasma (physics), plasma: ionized gas that responds to electric fields. Plasma televisions were the first large (over 32 inches diagonal) flat panel displ ...
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 imaging ...
(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
Web 2.0 (also known as participative (or participatory) web and social web) refers to websites that emphasize user-generated content, ease of use, participatory culture and interoperability (i.e., compatibility with other products, systems, and ...
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
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around to around . This is roughly between the upper ...
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 (business), distribution of sound, audio or video content to a dispersed audience via any electronic medium (communication), mass communications medium, but typically one using the electromagnetic spectrum (radio ...
the signal to individual television receivers. Alternatively television signals are distributed by
coaxial cable or optical fiber,