diff --git a/episodes/functions.md b/episodes/functions.md
index c9680d42..82406cab 100644
--- a/episodes/functions.md
+++ b/episodes/functions.md
@@ -110,7 +110,7 @@ round(3.712, 1)
## Use the built-in function `help` to get help for a function.
-Every built-in function has online documentation. You can always access the documentation using the built-in `help()` function. In the jupyter environment, you can access help by either adding a `?` at the end of your function and running it or Hold down Shift, and press Tab when your insertion cursor is in or near the function name.
+Every built-in function has [online documentation](https://docs.python.org/3/builtins/functions.html). You can always access the documentation using the built-in `help()` function. In the jupyter environment, you can access help by either adding a `?` at the end of your function and running it or Hold down Shift, and press Tab when your insertion cursor is in or near the function name.
```python
help(round)