Editing Creational pattern (section)

==Overview==
Creational design patterns are composed of two dominant ideas. One is encapsulating knowledge about which concrete [[Class (computer programming)|classes]] the system uses. Another is hiding how [[Instance (computer science)|instances]] of these concrete classes are created and combined.<ref>{{cite book|title=Design Patterns|year=1995|publisher=Addison-Wesley|location=Massachusetts|isbn=978-0-201-63361-0|last1=Gamma|first1=Erich|last2=Helm|first2=Richard|last3=Johnson|first3=Ralph|last4=Vlissides|first4=John|page=[https://archive.org/details/designpatternsel00gamm/page/81 81]|access-date=2015-05-22|url=https://archive.org/details/designpatternsel00gamm/page/81}}</ref>

Creational design patterns are further categorized into object-creational patterns and class-creational patterns, where object-creational patterns deal with object creation and class-creational patterns deal with class-instantiation. In greater details, object-creational patterns defer part of its object creation to another object, while class-creational patterns defer its object creation to subclasses.<ref>{{cite book|title=Design Patterns|year=1995|publisher=Addison-Wesley|location=Massachusetts|isbn=978-0-201-63361-0|last1=Gamma|first1=Erich|last2=Helm|first2=Richard|last3=Johnson|first3=Ralph|last4=Vlissides|first4=John|access-date=2015-05-22|url=https://archive.org/details/designpatternsel00gamm}}</ref>

Five well-known design patterns that are parts of creational patterns are the
* [[abstract factory pattern]], which provides an interface for creating related or dependent objects without specifying the objects' concrete classes.<ref>
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* [[builder pattern]],  which separates the construction of a complex object from its representation so that the same construction process can create different representations.
* [[factory method pattern]], which allows a class to defer instantiation to subclasses.<ref>
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* [[prototype pattern]], which specifies the kind of object to create using a prototypical instance, and creates new objects by cloning this prototype.
* [[singleton pattern]], which ensures that a class only has one instance, and provides a global point of access to it.<ref>
{{cite book|last1=Freeman|first1=Eric|last2=Freeman|first2=Elisabeth|last3=Sierra|first3=Kathy|last4=Bates|first4=Bert|editor-last=Hendrickson|editor-first=Mike|editor2-last=Loukides|editor2-first=Mike|year=2004|title=Head First Design Patterns|publisher=O'Reilly Media|location=California|isbn=978-0-596-00712-6|page=177|access-date=2015-05-22|url=http://shop.oreilly.com/product/9780596007126.do}}</ref>