diff --git a/023.slideshow/README.md b/023.slideshow/README.md
index 23f37fb..a9aa1ea 100644
--- a/023.slideshow/README.md
+++ b/023.slideshow/README.md
@@ -1,6 +1,18 @@
 photo slideshow
 ===============
 
+The main theme of this demo is trackloading data whilst the application is running.
+
+We cram a DD floppy full of image and music data, then load and display each image in turn whilst playing a P61 module.
+
+There are quite a few new things in here:
+
+    (1) We use a [modified bootloader](alpine_bootloader.s) that reads the size of the main program from the disk before trackloading it.
+    (2) Photon's trackloader is also now copied into the main program so it can be used to load subsequent data.
+    (3) We use multiple sections and a [linker script](link.script) to help with organising data on the ADF image. The linker script is not technically required, however I wanted to see what I could do with vlink and linker scripts.
+    (4) We switched to the [doynamite68k](https://github.com/AxisOxy/Planet-Rocklobster/tree/master/tools/doynamite68k) compressor/decompressor. The compressed file are larger than those generated by Shinkler, however the decompressor is a lot faster.
+    (5) P61 is configured to use CIA mode.
+
 try it
 ------
   * [Download disk image](bin/slideshow.adf?raw=true)