Need Help with PKI!

I understand the gist of how PKI works, but I'm still struggling with parts of it. I'm wondering if anyone has or knows about any documents that give good analogies about PKI. I know facts, but I need to get a better understanding of PKI. Any help will be appreciated.
The only thing that can stop you is you
Currently studying for 70-293
Currently studying for 70-293
Comments
Recent: 11/2019 - RHCSA (RHEL 7); 2/2019 - Updated VCP to 6.5 (just a few days before VMware discontinued the re-cert policy...)
Working on: RHCE/Ansible
Future: Probably continued Red Hat Immersion, Possibly VCAP Design, or maybe a completely different path. Depends on job demands...
Microsoft Windows Server(TM) 2003 PKI and Certificate Security
I only read about half the book before the exam, but it helped. This book really should be required reading for the 293 exam.
Absolutely +1. I'm working my way through it now and will be getting the updated 2008 edition as well.