Software design pattern

A software design pattern describes a reusable solution to a commonly needed behavior in software. A design pattern is not a rigid structure to be copied directly into source code. Rather, it is a description of and a template for solving a particular type of problem that can be used in many different contexts, including different programming languages and computing platforms. Design patterns can be viewed as formalized best practices that the programmer may use to solve common problems when designing software.

Object-oriented design patterns typically show relationships and interactions between classes or objects, without specifying the final application classes or objects that are involved.