There are many design pattern types for software design, each with their own merits and detractors.  RJLG’s use of several patterns capitalizes on the advantages of these types, while reducing the detriments.  Object oriented design requires the designers to define procedures within a system as objects.  The development is based upon objects interactions with other objects within the system.  This solves many of the problems designers typically encounter.  Contemporary design patterns attempt to streamline the design process with rapid iterations and evolving concepts.  Conventional design focuses on pre-design effort so that a plan is developed which detects errors as early as possible.