what is Gang of Four design pattern

Question

I have recently come to know that there is a design pattern in Java called Gang of Four (GoF). I'm not able to understand what it is and what's its use. Can anybody make me clear on this? Thanks in advance.

Answer 1

The authors of the DesignPatternsBook came to be known as the "Gang of Four." The name of the book ("Design Patterns: Elements of Reusable Object-Oriented Software") is too long for e-mail, so "book by the gang of four" became a shorthand name for it.

After all, it isn't the ONLY book on patterns. That got shortened to "GOF book", which is pretty cryptic the first time you hear it.

Source: http://c2.com/cgi/wiki?GangOfFour

Answer 2

Gang Of Four (GOF) refers to the authors of the book:

Design Patterns: Elements of Reusable Object-Oriented Software

From WIKI:

Design Patterns: Elements of Reusable Object-Oriented Software is a software engineering book describing recurring solutions to common problems in software design. The book's authors are Erich Gamma, Richard Helm, Ralph Johnson and John Vlissides with a foreword by Grady Booch. The authors are often referred to as the Gang of Four, GoF,or Go4

Answer 3

Gang of Four is not a design pattern, it is the colloquial name for the book "Design Patterns: Elements of Reusable Object-Oriented Software" by Erich Gamma, Richard Helm, Ralph Johnson and John Vlissides (hence Gang of Four). Note that Gang of Four or GoF is used to refer to either the group of authors or the book itself.

See also http://en.wikipedia.org/wiki/Design_Patterns