In this paper, we analyze workflow management system in programming language aspects. Many workflow characteristics such as workflow relevant data, workflow control structures, and workflow application invocations are studied and compared with those of distributed parallel programs. Although there exist minor differences between them, we found that there exist surprisingly many analogies between them. Based on this observation, we suggest to view workflow management system as distributed parallel program development platform. This new view on workflow management system provides users consistent view on workflow and workflow management system and with this view workflow management system designer can cope with arbitrary requests from the users keeping design consistency. Moreover the analogy between workflow and program provides a basis to apply program analysis techniques to the analysis of workflow.