Evolutionary algorithms (EAs) produce a vast amount of data by recurring processes, e.g., selection, recombination, or mutation, that work on populations of solutions for a specific problem. In order to get a better insight into the progress of EAs a Java-based visualization tool, called EAVis, was developed. Several coordinated views help the user to watch each generation step of the EA and to derive knowledge as well as better understanding of the underlying evolutionary computational models.