diff --git a/src/praktikum4/pangapass.java b/src/praktikum4/pangapass.java
index 0737ea3..5d0935d 100644
--- a/src/praktikum4/pangapass.java
+++ b/src/praktikum4/pangapass.java
@@ -4,6 +4,12 @@ public class pangapass {
 
 	public static void main(String[] args) {
 		for (int i = 0; i <= 9999; i++) {
+			// java string format magic
+			// % - start of a format token
+			// 04 - add 4 leading zeros
+			// d - type is int
+			// % - start of a new format token
+			// n - inserts a new line
 			System.out.printf("%04d%n", i);
 		}
 	}