copy() Operation

set aClonedObject = anObject.copy()

Creates an independent copy of the object it is applied to.

The Designer distinguishes between referencing and copying object nodes. If you have two objects of same type, for example item1 and item2, you can write set item2 = item1 thus assigning item2 a reference to item1. This means, if you later on modify any attribute values of item1, object item2 will also have these changed values.
Contrary to this situation, if you write set item2 = item1.copy(), changes in the state of item1 will not effect item2 (

This is explained in detail on Object References.

 anObject

Any object.