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object (instance, instance: instance is used when you are talking about the role with respect to the class and object is used when talking in a more general way)
subject			fact

object	is a synonym of instance
	can be referred to without reference to the data (instance variables) contained in it
	can be referred to by several different variables at the same time
	can represent any entity to which you can associate properties and behaviour
	has definition A data element in an object-oriented system, which has its own identity, belongs to a particular class, and has behaviour and properties
	has live activation while the object is performing computations in a sequence diagram
	has behaviour
	has state
	has synonym instance: instance is used when you are talking about the role with respect to the class and object is used when talking in a more general way
	is distinct from every other object even if they contain the same data
	is in a state until an event occurs that causes it to change state
	is structured
	is a subtopic of 2.1 - What is Object Orientation?
	is drawn as a rectangle containing a colon and the underlined name of the class (optional if it is clear from the context), which may be preceded by an optional instance name in a UML instance diagram
	is a kind of data item

Kinds of object :

• immutable object (3 facts) - an object that has a state which never changes after creation
• instance of user interface class (4 facts)
• Java object (3 kinds, 7 facts)
• occurrence (4 facts) - An object that is a member of a set of classes that set share common information but also differ from each other in important ways