K L University
System Metaphor is one of the core practices of XP as proposed by Kent Beck. The Metaphor is intended to contribute to the XP value of communication. Metaphor can be described as a means of communication among team members and clients. Unfortunately, Metaphor is poorly understood and this practice is commonly chosen to ignore by most of the XP teams. This paper elucidates the metaphor's contribution to the software architecture. This analysis will encourage XP teams to continue the usage of metaphors to strengthen their development practices. This paper focused on the appraising criteria for system metaphors and classified them into good, meager and ambiguous metaphors and elucidated the characteristics of a good metaphor and how it augments the four values of XP.