As I put in the title above, I've read through the Player's Handbook, and I've looked at Passive Perception and how it works on D&D Beyond, alongside some random Google Searches, but I don't quite have a cognitive grasp on it.

Maybe it's my ADHD, and/or my perception of Passive Perception, but maybe someone could try and explain how it works, and the dice math it entails?

It would be amazing if all of you who read this take a shot at explaining it to me, and maybe one or more of your explanations will make sense to me in a way I can understand!

Thanks for reading this if you did!

EDIT: I would like to thank everyone who helped me understand! I see now that I was confusing Passive Perception with Active Perception Checks, as the difference between the two is actually more straightforward than I had interpreted it to be!

:)