The TCollection class represents a list of TCollectionItem descendant class instances, and is used to create lists of instances that can be automatically persisted at design-time and run-time. For example, the standard component library uses the TCollection class as the ancestor for the TDataColumns class so that TDataSet instance columns can be persisted with forms.
Collections always own all items in the collection and will automatically dispose of all items in the collection when the collection is destroyed.