- level graphics toolkit or library such as the

Visualization of computer programs, particularly parallel programs, promises to help programmers better understand, develop, and debug their code, especially if the visualizations are relatively easy to create. We have developed a visualization methodology being used as a component in a comprehensive parallel program visualization system. The focus of the system is on application-specic user-tailored program views. An application-specic visualization of a parallel program presents the inherent application domain, semantics, and data being manipulated by the program in a manner natural to one's understanding of the program. In this paper we discuss why application-specic views are necessary for program debugging, and we list several requirements and challenges that a system for application-speciic viewing should meet. The visualization methodology that we introduce includes primitives for designing smooth animation scenarios, and most importantly, for allowing designers to visualize or showcase the concurrency exhibited by parallel programs.