View source for Wireless Markup Language

{{short description|Markup language for WAP pages}}
{{Infobox technology standard
| title             = Wireless Markup Language
| image             = 
| caption           = 
| status            = obsolete
| year_started      = 
| first_published   = {{Start date|1998|||}}
| version           = 
| version_date      = 
| preview           = 
| preview_date      = 
| organization      = [[WAP Forum]]
| committee         = 
| editors           = 
| authors           = 
| base_standards    = 
| related_standards = {{Unbulleted list|
 | [[Handheld Device Markup Language|HDML]]
 | TTML
 | [[Extensible Markup Language|XML]]
}}
| abbreviation      = WML
| license           = 
| website           = 
}}

'''Wireless Markup Language''' (WML),  based on [[XML]], is an obsolete [[markup language]] intended for devices that implement the [[Wireless Application Protocol]] (WAP) specification, such as [[mobile phones]]. It provides navigational support, data input, hyperlinks, text and image presentation, and forms, much like [[HTML]] (Hypertext Markup Language). It preceded the use of other markup languages used with WAP, such as [[XHTML]] and HTML itself, which achieved dominance as processing power in mobile devices increased.

==WML history==
[[Image:Mobile Web Standards Evolution Vector.svg|thumb|upright=1.3|right|Evolution of mobile web standards]]
Building on Openwave's [[Handheld Device Markup Language|HDML]], Nokia's "Tagged Text Markup Language" (TTML) and Ericsson's proprietary markup language for mobile content, the [[WAP Forum]] created the WML 1.1 standard in 1998.<ref>[https://inspiredbloggers.blogspot.com/2004/12/brief-history-of-wap_110252445307049372.html The HCI blog: A brief History of WAP]</ref> WML 2.0 was specified in 2001,<ref>WAP Forum: [http://www.wapforum.org/DTD/wml20.dtd "Wireless Markup Language (WML) 2.0 Document Type Definition"]</ref> but has not been widely adopted. It was an attempt at bridging WML and [[XHTML Basic]] before the [[WAP 2.0]] spec was finalized.<ref>Openwave Developer Network: [http://developer.openwave.com/dvl/support/documentation/guides_and_references/xhtml-mp_style_guide/chapter1.htm "One quick note about WML 2.0"]</ref> In the end, [[XHTML Mobile Profile]] became the markup language used in WAP 2.0. The newest WML version in active use is 1.3.

The first company to launch a public WML site was Dutch [[mobile phone]] network operator [[Telfort]] in October 1999 and the first company in the world to launch the [[Nokia 7110]]. The [[Telfort]] WML site was created and developed as side project to test the device's capabilities by a billing engineer called Christopher Bee and National Deployment Manager, Euan McLeod. The WML site consists of four pages in both Dutch and English that contained many grammatical errors in Dutch as the two developers were unaware the WML was configured on the [[Nokia 7110]] as the home page and neither were native Dutch speakers.

==WML markup==
WML documents are XML documents that validate against the WML DTD ([[Document Type Definition]])<ref>WAP Forum: [http://www.wapforum.org/DTD/wml13.dtd "Wireless Markup Language (WML) 1.3 Document Type Definition"]</ref>
. The W3C Markup Validation service (http://validator.w3.org/) can be used to validate WML documents (they are validated against their declared document type).

For example, the following WML page could be saved as "example.wml":

<syntaxhighlight lang="xml">
<?xml version="1.0"?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN"
   "http://www.wapforum.org/DTD/wml_1.1.xml" >
<wml>
  <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
  </head>
  <card id="main" title="First Card">
    <p mode="wrap">This is a sample WML page.</p>
  </card>
</wml>
</syntaxhighlight>

A WML document is known as a "deck". Data in the deck is structured into one or more "cards" (pages), each of which represents a single interaction with the user.

WML decks are stored on an ordinary [[web server]] configured to serve the text/vnd.wap.wml [[MIME type]] in addition to plain HTML and variants. The WML cards when requested by a device are accessed by a bridge ([[WAP gateway]]), which sits between mobile devices and the World Wide Web, passing pages from one to the other much like a [[Proxy server|proxy]]. The gateways send the WML pages on in a form suitable for mobile device reception ([[WBXML|WAP Binary XML]]).  This process is hidden from the phone, so it may access the page in the same way as a browser accesses [[HTML]], using a URL (for example,  <nowiki>http://example.com/foo.wml</nowiki>). (Provided the mobile phone operator has not specifically locked the phone to prevent access of user-specified URLs.)

WML has a scaled-down set of procedural elements, which can be used by the author to control navigation to other cards.

Mobile devices are moving towards allowing more [[XHTML]] and even standard HTML as processing power in handsets increases. These standards are concerned with formatting and presentation.  They do not however address cell-phone or mobile device hardware interfacing in the same way as WML.

== WML capability in desktop browsers ==
[[File:Wmlbrowser-text-decoration.png|thumb|Screenshot of WMLBrowser on Mozilla Firefox]]
The [[Presto (layout engine)|Presto]] layout engine (used by [[Opera (browser)|Opera]] before its switch to [[Blink (layout engine)|Blink]]) understood WML natively. [[Mozilla]]-based browsers ([[Firefox]] (before version 57), [[SeaMonkey]], [[MicroB]]) could interpret WML through the WMLBrowser add-on. [[Google Chrome]] can also interpret WML via two extensions: WML and FireMobileSimulator.
{{-}}

==Criticism==
{{main article|Wireless Application Protocol#Criticism}}

==See also==
*[[WMLScript]]
*[[Handheld Device Markup Language]]
*[[Wireless Application Protocol Bitmap Format]]
*[[Mobile browser]]
*[[List of document markup languages]]
*[[Comparison of document markup languages]]
*[[XHTML Mobile Profile]]

==References==
{{Reflist}}

==External links==
*[http://www.wapforum.org/what/technical.htm Technical Specifications at the WAP Forum]
*[http://www.passani.it/gap/ XHTML-MP Authoring Practices]
*[http://www.openmobilealliance.org/ Open Mobile Alliance]

{{Open Mobile Alliance standards}}
{{Document markup languages}}

{{Authority control}}

[[Category:Wireless Application Protocol]]
[[Category:Open Mobile Alliance standards]]
[[Category:XML markup languages]]