Infinite Mac: Resource Fork Roundtripping

I love(d) resource forks. Before there were signed applications, it made it easy to modify applications without the source code. I even had a plug-in that disassembled the binary executable blobs, and had fun modifying one of the original text editor desk accessories to allow windows larger than 512 x 342. (Those were the days...)

The resource fork concept was always something that confused me about old mac. Anyone have a recommended blog/guide to learn more about how that works?