1.abstractfactory
2.factory method
3.builder
4.prototype
5.singleton
6.adapter
7.bridge
8.decorator
9.composite
10.facade
11.proxy
12.chainof reponsiblity
13.command
14.interpretor
15.itertor
16.mediator
17.memento
18.observer
19.state
20.strategy
21.template factory
22.visitor
23.flyweight
