Name for lock parts: pins or tumblers?

Up until today I thought the moving parts inside a lock, the things that need to line up just so if you want to turn the key and open the lock, are called "tumblers". But after someone said they didn't know what tumblers were I second guessed myself and looked up "lock diagram" on DDG to see how diagrams referred to these parts. All the diagrams on the first page of my search referred to them as pins instead. I 've seen that before too but it's not as salient to me as tumblers.

Then I...

Name for lock parts: pins or tumblers?