GUPRO - Generic Understanding of Programs An Overview. GUPRO is an integrated workbench to support program understanding of heterogenous software systems on arbitrary levels of granularity. GUPRO can be adapted to specific needs by an appropriate conceptual model of the target software. GUPRO is based on graph-technology. It heavily relies on graph querying and graph algorithms. Source code is extracted into a graph repository which can be viewed by an integrated querying and browsing facility. For C-like languages GUPRO browsing includesa complete treatment of preprocessor facilities.