A representation of a markup language data such as XML expressed as a sequence of encoded items provides a data format including a type field containing i) a construct type identifying a type of markup language data construct to which the encoded item corresponds or, ii) a directive type identifying directive information concerning a processing characteristic associated with the sequence of encoded items. If the type field contains a construct type, the encoded item includes i) a length field containing a size of construct data associated with the markup language data construct to which the encoded item corresponds and ii) a value field identifying construct data associated with the markup language data construct to which the encoded item corresponds. For a directive type, the encoded item includes a directive value supplementing the directive information concerning a processing characteristic associated with the sequence of encoded items.