One of the first companies to pioneer the concept of pull - based information services on a mobile device was Unwired Planet, based in California. Launched in 1996, the company produced a system called UP.Link, comprised of a software browser (UP.Browser) that ran on PDAs and mobile handsets, and a network - side gateway that would aid the browser in fetching and formatting sites written in the company ’ s proprietary markup language, HDML.
HDML was a card - based system for structuring content, and it bore little resemblance to HTML,
even in its simplest form. The basic principle was that the browser would retrieve a “ deck ” of such cards, allowing a user to look at a selection of related pages of information without the browser having to make additional requests to the server. The cards supported textual and basic image content, and allowed users to navigate through decks with simple links and soft - key anchors; it even initiated telephone calls.
In the U.S., AT & T ran a packet - switched data network called PocketNet, which was, at the time, one of the first consumer offerings to provide Web - like access on a mobile device. This service encouraged many early website owners to experiment with developing HDML - based sites for this niche U.S. market.
In 1997, Unwired Planet attempted, and failed, to get HDML adopted as a markup standard by the W3C, which would have been an important step in getting the technology widely used and used outside of the United States. However, in that year, Unwired Planet joined with Nokia and Ericsson (which had been developing Web - like markup languages of their own) to form the WAP Forum, a standards body that would go on to specify WAP and related standards. Much of the early structure of the resulting WML markup language came from the HDML syntax and concepts, and Unwired Planet adapted their infrastructure and browsers to support WAP, becoming a major worldwide vendor of browser and gateway products as a result.
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