We all know the value of design experience. How many times have you had the feeling that you've solved a problem before but not knowing exactly
where or how?
If you could remember the details of the previous problem and how you solved it, then you could reuse the experience instead of rediscovering it.
However, we do not do a good job of recording experience in software design for others to use.
Each design pattern systematically names and evaluates an important and recurring design in object-oriented systems.
Our goal is to capture design experience in a form that people can use effectively.
To this end gofpatterns.com has documented some of the most important design patterns and presents them as a catalog.
Design patterns make it easier to reuse successful designs and architectures.
Expressing proven techniques as design patterns makes them more accessible to developers of new systems.
Design patterns help you choose design alternatives that make a system reusable and avoid alternatives that compromise reusability.
Design patterns can even improve the documentation and maintenance of existing systems by furnishing an explicit specification of class and object interactions
and their underlying intent. Put simply, design patterns help a designer get a design "right" faster.
The following discusses the elements of design patterns.
Design Pattern Elements