**Heapsort** is a _comparison-based_ sorting algorithm. It can be thought of as an improved selection sort. It divides its input into a sorted and an unsorted region, and it iteratively shrinks the unsorted region by extracting the largest element and moving that to the sorted region.

[quick-wiki]: https://en.wikipedia.org/wiki/Quicksort

[quick-image]: https://upload.wikimedia.org/wikipedia/commons/6/6a/Sorting_quicksort_anim.gif "Quick Sort"

[heap-wiki]: https://en.wikipedia.org/wiki/Heapsort

[radix-wiki]: https://en.wikipedia.org/wiki/Radix_sort