希尔排序(Shell Sort)是插入排序的一种。也称缩小增量排序，是直接插入排序算法的一种更高效的改进版本。希尔排序是非稳定排序算法。该方法因DL．Shell于1959年提出而得名。
希尔排序是把记录按下标的一定增量分组，对每组使用直接插入排序算法排序；随着增量逐渐减少，每组包含的关键词越来越多，当增量减至1时，整个文件恰被分成一组，算法便终止。(Hill sorting (Shell Sort) is a sort of insertion sort. Also known as narrowing incremental sort, is a more efficient version of the direct insertion sort algorithm. The Hill sort is an unstable sorting algorithm. The method was named after DL.Shell was put forward in 1959.
The Hill sort is grouped by a certain increment of the record. Each group uses direct insertion sort algorithm. As the increment gradually decreases, each group contains more and more keywords. When the increment is reduced to 1, the whole file is divided into one group and the algorithm terminates.)