I only understand part of it and confused so please shed some lights or explain to me the differences:

As I understand Monitoring Template had nothing to do with Notification rules so the purpose of Monitoring Template is for create a Template and apply to All of the instance so that DBAs doesn't have to customize for each DBs. ok, that's great but then what can you do after that once you have the template build and assign to all DBs?

Notification Rules is where you can build rules which will notify DBAs via email, should anything warnings, errors, etc.. may happened to DBs, server, agent etc....

Do I understand this correctly? Please input some advises.

thanks