Unlike previous Canon DSLR cameras the Canon 600D includes a few booklets on photography and how to get the best out of your camera. This is a great idea, good publicity for Canon and a way to help new photographers learn more about their camera than the manual can show.
The booklets are:
1) Using Image Stabilised Lenses for Better Results
2) Do More With Macro
3) Flash Classroom
The flash manual is a particularly good idea as the Canon 600D includes control for off camera flashes - a first for this range of camera which started with the Canon 300D back in 2003.