In conventional programming approach programming is sequential task that is performed in three sequential steps, first one is designing, then coding/programming and then debugging. On the other hand, Knowledge engineering, we are designing the Expert System that involve different activities like assessment, knowledge acquisition, design, testing, documentations and maintenance. In Conventional programming we only focuses on solution of the problem while in Expert System ES programming focuses in problem. In Knowledge Engineering main philosophy on right knowledge base, because solution will be derived from the generic reasoning machine.