# Line 21

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> Markdown URL: https://mediated.wiki/source/Line_21.md
> Source: https://en.wikipedia.org/wiki/Line_21
> Source revision: 1294297172
> License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/)

'''Line 21''' may refer to:

==Closed Captioning==
* [EIA-608](/source/EIA-608), a standard for closed captioning for NTSC TV broadcast, also known as "line 21 captions"
==Telecommunications==
Line 21, a Hungarian telecommunications company [Vodafone Hungary](/source/Vodafone_Hungary)

==Railway Line==
===In operation===
* [Line 21 (Guangzhou Metro)](/source/Line_21_(Guangzhou_Metro)), a metro line of the  Guangzhou Metro in China
* [Line 21 (Zürich)](/source/Line_21_(Z%C3%BCrich)), Switzerland 
* [Yangluo Line](/source/Yangluo_Line), a metro line of the Wuhan Metro in China

===Under Planning===
* [Line 21 (São Paulo Metro)](/source/Line_21_(S%C3%A3o_Paulo_Metro)), a future metro line of the São Paulo metro
* [Line 21 (Shanghai Metro)](/source/Line_21_(Shanghai_Metro)), a future metro line of Shanghai Metro

{{disambig}}

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Adapted from the Wikipedia article [Line 21](https://en.wikipedia.org/wiki/Line_21) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Line_21?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.