What is the difference between the CNS and the PNS?

The CNS sends messages through the conscious part of your brain, so you make a decision about what to do. For example, if you see a piece of cake and you want to eat it, a message travels to your CNS, your Brain makes a decision, and tells you to pick it up. This makes the CNS decision making process slower.

The PNS doesn't involve the conscious part of the brain. sometimes, the messages don't even go to the brain at all. The PNS is used for things such as breathing or running away from danger, where it would take too long to think about it. This makes the PNS faster.