This simple architecture is overlaid by a number of special structures which the Z-machine maintains inside memory. The Z-machine is primarily used for adventure games, where the dictionary holds names of items and verbs that the player might type, and the objects tend to be the places and artifacts which make up the game. Each object in the tree may have a parent , a sibling and a child . There is a small mailbox here. Opening the small mailbox reveals a leaflet.
Attributes are simply flags, that is, they can be set or unset, but have no numerical value.
Properties hold numbers, which may in turn represent pieces of text or other information. One of the attributes of the mailbox object is set to indicate that it's a container, whereas the same attribute for the leaflet object is unset. Z-machine programs are stored on disc, or archived on the Internet, in what are called story files . A story file consists of a snapshot of main memory only. The processor begins to run a story file by starting with an empty stack and a PC value set according to some information in the story file's header.