TYPES OF OBJECTS 

There are 4 types of objects: things, players, exits, and rooms. The 
first letter following an object's ID number indicates the type: 
P(layer), E(xit), R(oom), otherwise, thing. Things are inanimate 
objects that can be carried. Players are animate objects that can move 
and carry. Exits are the means by which objects move. Rooms are 
locations that contain objects and linked  exits.