There is more than one way to accelerate decarbonization

While West Virginia's Senator Joe Manchin is doing his best to block climate policy and save his state's dying fossil fuel industry, there is no reason to believe that the proposed "Clean Electricity Program" policy design ...

A potential model for a real physical warp drive

A pair of researchers at Applied Physics has created what they describe as the first general model for a warp drive, a model for a space craft that could travel faster than the speed of light, without actually breaking the ...

TV viewers with second screen, second sight

More and more of us choose to watch television while using our smartphones and tablets. This second-screen viewing behavior often means that viewers are less engaged with the television programming and advertising than they ...

Laura's leftovers move east, leaving a disaster in Louisiana

The remnants of Hurricane Laura unleashed heavy rain and twisters hundreds of miles inland from a path of death and mangled buildings along the Gulf Coast, and forecasters warn of new dangers as the tropical weather blows ...

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Television

Television (TV) is a widely used telecommunication medium for transmitting and receiving moving images, either monochromatic ("black and white") or color, usually accompanied by sound. "Television" may also refer specifically to a television set, television programming or television transmission. The word is derived from mixed Latin and Greek roots, meaning "far sight": Greek tele (τῆλε), far, and Latin visio, sight (from video, vis- to see, or to view in the first person).

Commercially available since the late 1930s, the television set has become a common communications receiver in homes, businesses and institutions, particularly as a source of entertainment and news. Since the 1970s the availability of video cassettes, laserdiscs, DVDs and now Blu-ray discs, have resulted in the television set frequently being used for viewing recorded as well as broadcast material.

Although other forms such as closed-circuit television are in use, the most common usage of the medium is for broadcast television, which was modeled on the existing radio broadcasting systems developed in the 1920s, and uses high-powered radio-frequency transmitters to broadcast the television signal to individual TV receivers.

Broadcast TV is typically disseminated via radio transmissions on designated channels in the 54-890 megahertz frequency band. Signals are now often transmitted with stereo and/or surround sound in many countries. Until the 2000s broadcast TV programs were generally recorded and transmitted as an analog signal, but in recent years public and commercial broadcasters have been progressively introducing digital television broadcasting technology.

A standard television set comprises multiple internal electronic circuits, including those for receiving and decoding broadcast signals. A visual display device which lacks a tuner is properly called a monitor, rather than a television. A television system may use different technical standards such as digital television (DTV) and high-definition television (HDTV). Television systems are also used for surveillance, industrial process control, and guiding of weapons, in places where direct observation is difficult or dangerous.

Amateur television (HAM TV or ATV) is also used for experimentation, pleasure and public service events by amateur radio operators. HAM TV stations were on the air in many cities before commercial TV stations came on the air.

This text uses material from Wikipedia, licensed under CC BY-SA