Changes

==Origin==

==Origin==

The etymology of "radio" or "radiotelegraphy" [[reveals]] that it was called "[http://en.wikipedia.org/wiki/Wireless_telegraphy wireless telegraphy]", which was shortened to "wireless" in Britain. The prefix ''radio''- in the sense of wireless transmission, was first recorded in the word radioconductor, a [[description]] provided by the French physicist [http://en.wikipedia.org/wiki/%C3%89douard_Branly Édouard Branly] in 1897. It is based on the verb to [[radiate]] (in Latin "radius" means "spoke of a wheel, beam of [[light]], ray"). This [[word]] also appears in a 1907 article by [http://en.wikipedia.org/wiki/Lee_De_Forest Lee De Forest], it was adopted by the [http://en.wikipedia.org/wiki/United_States_Navy United States Navy] in 1912, and became common by the time of the first commercial broadcasts in the United States in the 1920s. (The noun "broadcasting" itself came from an [[agricultural]] term, meaning "scattering [[seeds]] widely".) The term was then adopted by other [[languages]] in Europe and Asia. British Commonwealth countries continued to mainly use the term "wireless" until the mid-20th century, though the magazine of the [http://en.wikipedia.org/wiki/BBC BBC] in the UK has been called [http://en.wikipedia.org/wiki/Radio_Times Radio Times] ever since it was first published in the early 1920s.

The etymology of "radio" or "radiotelegraphy" [[reveals]] that it was called "[https://en.wikipedia.org/wiki/Wireless_telegraphy wireless telegraphy]", which was shortened to "wireless" in Britain. The prefix ''radio''- in the sense of wireless transmission, was first recorded in the word radioconductor, a [[description]] provided by the French physicist [https://en.wikipedia.org/wiki/%C3%89douard_Branly Édouard Branly] in 1897. It is based on the verb to [[radiate]] (in Latin "radius" means "spoke of a wheel, beam of [[light]], ray"). This [[word]] also appears in a 1907 article by [https://en.wikipedia.org/wiki/Lee_De_Forest Lee De Forest], it was adopted by the [https://en.wikipedia.org/wiki/United_States_Navy United States Navy] in 1912, and became common by the time of the first commercial broadcasts in the United States in the 1920s. (The noun "broadcasting" itself came from an [[agricultural]] term, meaning "scattering [[seeds]] widely".) The term was then adopted by other [[languages]] in Europe and Asia. British Commonwealth countries continued to mainly use the term "wireless" until the mid-20th century, though the magazine of the [https://en.wikipedia.org/wiki/BBC BBC] in the UK has been called [https://en.wikipedia.org/wiki/Radio_Times Radio Times] ever since it was first published in the early 1920s.

*[http://en.wikipedia.org/wiki/19th_century 1887]

*[https://en.wikipedia.org/wiki/19th_century 1887]

==Definitions==

==Definitions==

*1: of, relating to, or operated by [[radiant]] [[energy]]

*1: of, relating to, or operated by [[radiant]] [[energy]]

:d : [[controlled]] or directed by radio  

:d : [[controlled]] or directed by radio  

==Description==

==Description==

'''Radio''' is the transmission of [[signals]] through free [[space]] by modulation of [[electromagnetic]] waves with [[frequencies]] below those of visible [[light]]. [[Electromagnetic]] radiation travels by means of oscillating electromagnetic fields that pass through the air and the [[vacuum]] of [[space]]. [[Information]] is carried by systematically changing (modulating) some property of the radiated [[waves]], such as [http://en.wikipedia.org/wiki/Amplitude amplitude], [[frequency]], phase, or [[pulse]] width. When radio waves pass an electrical conductor, the oscillating fields induce an alternating current in the conductor. This can be detected and [[transformed]] into sound or other signals that carry [[information]].[http://en.wikipedia.org/wiki/Radio]

'''Radio''' is the transmission of [[signals]] through free [[space]] by modulation of [[electromagnetic]] waves with [[frequencies]] below those of visible [[light]]. [[Electromagnetic]] radiation travels by means of oscillating electromagnetic fields that pass through the air and the [[vacuum]] of [[space]]. [[Information]] is carried by systematically changing (modulating) some property of the radiated [[waves]], such as [https://en.wikipedia.org/wiki/Amplitude amplitude], [[frequency]], phase, or [[pulse]] width. When radio waves pass an electrical conductor, the oscillating fields induce an alternating current in the conductor. This can be detected and [[transformed]] into sound or other signals that carry [[information]].[https://en.wikipedia.org/wiki/Radio]

[[Category: Physics]]

[[Category: Physics]]