Note about viz in the example
@@ -165,7 +165,8 @@ we can do something `n` times.
```
Then, the acutal implementation of multiplication using a while loop
-and addition.
+and addition. The `viz` submodule is not actually necessary. It just
+lets you see the value coming out of counter in the pictures.
``` racket
(define/module mult ((a : 32) (b : 32)) ((out : 32))
