A category for the item. Greater signs or slashes can be used to informally indicate a category hierarchy.

The subject matter of an object.

The object upon which the action is carried out, whose state is kept intact or changed. Also known as the semantic roles patient, affected or undergoer (which change their state) or theme (which doesn't). E.g. John read *a book*.

For failed actions, more information on the cause of the failure. Consider using the Error type.

The object that helped the agent perform the action. E.g. John wrote a book with *a pen*.

The result produced in the action. E.g. John wrote *a book*.

The item that is being reviewed/rated.

A goal towards an action is taken. Can be concrete or abstract.

The source or cause of the event.

A sub property of object. The options subject to this action.

Indicates the primary entity described in some page or other CreativeWork.

Indicates that the CreativeWork contains a reference to, but is not necessarily about a concept.

A piece of data that represents a particular aspect of a fictional character (skill, power, character points, advantage, disadvantage).

An item is an object within the game world that can be collected by a player or, occasionally, a non-player character.

The task that a player-controlled character, or group of characters may complete in order to gain a reward.

For itemListElement values, you can use simple strings (e.g. "Peter", "Paul", "Mary"), existing entities, or use ListItem.<br/><br/> Text values are best if the elements in the list are plain strings. Existing entities are best for a simple, unordered list of existing things in your data. ListItem is used with ordered lists when you want to provide additional context about the element in that list or when the same item might be in different places in different lists.<br/><br/> Note: The order of elements in your mark-up is not sufficient for indicating the order or elements. Use ListItem with a 'position' property in such cases.

An entity represented by an entry in a list or data feed (e.g. an 'artist' in a list of 'artists').

Things owned by the organization or person.

A sub property of object. The object that is being replaced.

A sub property of object. The object that replaces.

The thing -- flight, event, restaurant, etc. being reserved.

The tangible thing generated by the service, e.g. a passport, permit, etc.

A sub property of object. The collection target of the action.

The electronic systems used to play [video games](http://en.wikipedia.org/wiki/Category:Video_game_platforms).