diff --git a/Readme.md b/Readme.md
index 3cf4475..848c612 100644
--- a/Readme.md
+++ b/Readme.md
@@ -33,3 +33,8 @@ rajouter la définition de l'alias dans ~/.bashrc
 ```bash
 sed  's/^(#|$|\s+#.*)//g'  /etc/profile > profile
 ```
+
+## Sed
+```bash
+history  | awk '{print $4}' | sort  | uniq -c | sort -n
+```