Courage and being brave are easy to explain. I once knew a guy back in the military. Without going into too much detail, a member of the unit was injured but was able to get to cover. We had to extract,but due to injury, wasn't really able to move on his own. This guy went over to our comrade, picked him up, and carried him out. I noticed that the guy had wet himself. That is bravery. That is courage. Being so scared to do something that you literally wet yourself, but you do it anyway.
Beckett: Me too.
~When Castle and Beckett met Gene Simmons.