Items are the objects that you can hold or example or wear. They are sometimes also known as "objects" in the code and documentation, but that can also refer to mudobjects in general. Commonly used properties

short	a single noun
name	a noun phrase. must start with an indefinite article if appropriate - i.e. "a " or "an ", usually. avoid "some", have "a pair of" or whatever else is appropriate - for example "a pair of socks". if 'short' occurs in it, this will be highlighted. if short does not occur in it, then you should find some other 'main noun' and highlight that in object colour.
name.[0-9]	A state-sensitive version of name. Will only be used if the objects state is so, make sure you set a default 'name' also.
Plural flag	this should be set if the object is itself grammatically plural. For example, "a pair of scissors".
name.plural	Sometimes the auto-pluraliser gets things wrong. This property can be set to a plural version of the name if so. You should leave off the article/number.
long	a long noun phrase. This is shown in 'look' and 'list', where space is not at as much of a premium.
long.plural	plural version of above.
short_desc	appears in 'look' in preference to name and long. Not used in any other context. You can have a sentence here if you like.
short_desc.[0-9]	A state-sensitive version of the above. Will only be used if the objects state is so.
desc.from	Get all the descriptive text for this object from the object referenced in desc.from. If states description attributes exist on the desc.from object, the source object's state will be used to choose which one is shown.
desc.external	Descriptive text seen by someone outside the object examining it. Standard attribute set when using desc on objects or mobiles.
desc.internal	Descriptive text seen by someone inside the object looking. Standard attribute set when using desc on rooms.
desc.[0-9].internal desc.[0-9].external	State sensitive versions of the above. Will only be used if the objects state is so.
Stated flag	Are you using state on an object? Is it open=1, locked=2? No? Well, set Stated on it, to avoid embarassing incidents.
initstate	Initial state of an object - that it will start off at, and is reset to. Defaults to 0.
zone	The zone an object is associated with. This is what it will reset with and will save with. This can be different from the zone the object is physically contained within.
mass	the mass of the object in grams
ovolume	the volume the object takes up in millilitres
cost	how much an object will cost in a shop
onprep	Preposition used in place of 'on' in phrases like 'You are standing on the floor'.
format.possessable	If set to 0, actions targetted at dragged/mounted/sat-upon objects won't decorate the object's name with the possessor's
Danger flag	Dangerous objects cannot be given to mortals or mobiles, and mobiles won't pick them up.

Object discovery

discover	When the object is examined, the object referenced here will be moved to the examiner's location.
discover.%i	As above, but allows a number of objects to be moved simultaneously.
discover.count	Defines the number of objects listed in the discover array.
disc.%i	Like discover.%i, only the objects are cloned at the examiner's location, not moved.
disc.%i.count	Defines the number of clones to make for each entry in the disc array. Defaults to 1 if omitted.
disc.count	Defines the number of entries listed in the disc array.

The discovery stuff only happens once; the first time an object is examined after a reset.
%i refers to an integer number, greater than or equal to zero. Array.%i attributes should start at array.0

See also Clothing, Consumables, Liquids, Weapons

Containers

CONTAINER	You can put stuff in your object now! And take it out again!
volume	the capacity of the container (mils)
maxload	the maximum mass the container can hold (grams)
contains	This is a new (and as yet unused one). Say you have an egg carton. You want it to only be able to contain eggs, and 6 of them. How? Simply set volume and maxload to 6 * the egg's ovolume and mass. And then set 'contains' to example_egg_1. Then only example_egg_1 or things with a treatas set to it will be able to go in your egg carton.
container.location	For a worn container that covers multiple bodyparts (eg. arms and legs for a poacher's jacket) defines which area has the contents (eg. just the body). Important when wearing things on top of the container that might restrict access.