What are the modular pieces of Libp2p?

After watching several videos, I have noticed that there are different names for different modular ‘pieces’ of the libp2p project. I have seen:

  • Transports
  • Multiplexers
  • Secure Channels
  • Peer Discovery
  • Peer Routing
  • Content Routing
  • Nat Traversal
  • Pubsub

Identified as the pieces,but I’m not sure if this is the current, most used names. It would be helpful to have high level ~2 sentence summaries of these (how you would explain them to a kid) and also have it stated which layers each of the work upon.