diff --git a/stack.h b/stack.h
index f7d542d..243e8e8 100644
--- a/stack.h
+++ b/stack.h
@@ -9,6 +9,14 @@ The latest element is taken from the stack. */
 
 //TODO: passenden Datentyp als struct anlegen
 
+
+typedef struct Node{
+  int data;
+  struct Node *next;
+
+  } StackNode;
+
+
 // Pushes data as pointer onto the stack.
 StackNode *push(StackNode *stack, void *data);