HeapSort an implementation of Williams and Floyd's TopDown HeapSort. HeapSort is a fast internal sort written in Java that uses a sorting algorithm analogous to power struggles for higher positions in a hierarchical bureaucracy. Source provided. It is faster than QuickSort, but slower that RadixSort. It sorts using a comparison routine you provide to compare two elements to be sorted. May be freely distributed and used for any purpose except military. You can test it with: java.exe -jar heapsort.jar The icon represents the hierarchical structure of the heap created during the sort.