Slide 10.20: Line-by-line anatomy of DB.c   Slide 11.2: Microbrowsers   Home

WML (Wireless Markup Language)

---

The WAP (Wireless Application Protocol) is the leading standard for information services on wireless devices like smartphones. WAP is published by the WAP Forum, which is now consolidated into the Open Mobile Alliance (OMA). WML is part of the WAP and it is the language used to create pages to be displayed in a WAP browser.

WML
WML is a mark-up language inherited from HTML, but WML is based on XML, so it is much stricter than HTML. Pages in WML are called DECKS. Decks are constructed as a set of CARDS. Handheld devices are moving towards support for greater amounts of XHTML (Extensible HTML) and even standard HTML as processing power in handsets increases. It is likely WML will be phased out in the future.

WMLScript
WMLScript is a procedural scripting language for simple code run on the client. It is employed to complement WML. WMLScript is a light JavaScript language. However, WML scripts are not embedded in the WML pages. WML pages contains references to script URLs. WML scripts need to be compiled into byte code on a server before they can run in a microbrowser.

WAP Homepages
WAP homepages are not very different from HTML homepages. The markup language used for WAP is WML. WML uses tags—just like HTML—but the syntax is stricter and conforms to the XML 1.0 standard. WML pages have the extension *.WML, just like HTML pages have the extension *.HTML .

WML Tags
WML is mostly about text. Tags that would slow down the communication with handheld devices are not a part of the WML standard. The use of tables and images is strongly restricted. Since WML is an XML application, all tags are case sensitive and must be properly closed.