What would happen if you accidentally let go of your brake hand while on a rappel? And, what would occur if you let go of your brake hand after the climber you were belaying fell?What if you fell into a crevasse? How would you get out? Or, if you were injured in the crevasse, how would your partners rescue you? The best answer to all of the above questions, and to many more, is to properly learn how to use the Prusik knot as I carefully describe in...