Introduction
This is WAP, basically HTML for cellphones. Each .WML file is a deck, which is split into cards. One card is displayed at a time.
Ostensibly this allows multiple related pages to be hosted on the same file and thus not require delays or data transmission when moving between cards in the same deck.
A "card" in this context is not a poker card, rather, it is a text card, like those used by TV hosts and presenters.
Card: one part of a deck that is displayed at a time.
Deck: a series of cards that lie in a single .wml file.
HTML: markup language used by websites visited by full-fledged personal computers and advanced mobile devices.
WAP: Wireless Application Protocol, a standard intended for mobile devices so they can access the World Wide Web.