As someone trying to learn more about jaw surgery and what would help my aesthetic and functional issues, I found this guide helpful to understanding cephalometric data and terminology that I've encountered while trying to get a deeper understanding of relevant principles. It's been helpful when reading research papers and certain topics on this forum as well.
https://courses.washington.edu/predoc/Pediatric%20Dentistry/Ceph.Handout.docIf anyone knows of a better guide, or additional materials, feel free to post them here.