Extensible, multi-presentation content is created in human/machine readable
form, where each data object may contain numerous data elements that comprise alternate
representations of a single piece of information, such as audio, text transcription
of the audio, short-form summary of the text, and metadata concerning the story.
Advantageously, each data element is presentation-independent, meaning that it
does not require a particular type of presentation, such as HTML, WML, etc. Each
content instance thus provides raw data, leaving the end-user free to access the
data as desired. Specifications such as data type definitions (DTDS) may be used
to prescribe that each story include the constituent data elements, e.g., text,
audio, short-form text, metadata, etc. The DTDs define a dialect of extensible
Markup Language (XML). Further, different DTDs prescribe the format of each data
element. A developer may also define further DTDs defining additional data elements,
sub-elements, sub-sub-elements, and the like.