diff --git a/tech/quicksort.wiki b/tech/quicksort.wiki
index faf1604..8076e06 100644
--- a/tech/quicksort.wiki
+++ b/tech/quicksort.wiki
@@ -3,3 +3,6 @@
 Quicksort is a sorting algorithm that runs in `O(n log n)` time.
 
 == Algorithm ==
+
+For some array `arr`, chose come pivot value in `arr`. It does not matter how
+this pivot, `pvt` is chosen.