diff --git a/book/src/SUMMARY.md b/book/src/SUMMARY.md
index 2ea8f618..7e96fb03 100644
--- a/book/src/SUMMARY.md
+++ b/book/src/SUMMARY.md
@@ -8,4 +8,4 @@
         - [Windows setup]()
         - [Mac OS setup]()
     - [Building the game](./setup/building.md)
-- [Learn agb part I - pong](./pong/introduction.md)
\ No newline at end of file
+- [Learn agb part I - pong](./pong/01_introduction.md)
diff --git a/book/src/pong/introduction.md b/book/src/pong/01_introduction.md
similarity index 93%
rename from book/src/pong/introduction.md
rename to book/src/pong/01_introduction.md
index f27d5a21..85187fac 100644
--- a/book/src/pong/introduction.md
+++ b/book/src/pong/01_introduction.md
@@ -3,6 +3,7 @@
 In this section, we'll make a simple pong style game for the Game Boy Advance using `agb`.
 You will learn:
 
+* How to use tiled graphics modes.
 * How to import graphics using `agb`.
 * What Game Boy Advance sprites are and how to put them on the screen.
 * How to detect button input and react to it.