Charcoal is a highly reversible drawing medium. You can get rich dark tones out of it, with plenty of high contrast. The medium itself is known to inspire spontaneous and gestural marking as well as soft edges and smudging. Charcoal is a dry, dusty medium and tends to fly around on the page in a way that isn’t terribly controllable. It is not associated with a delicacy of mark-making the way graphite is. And, it’s often recommended to use spray fixative with charcoal to lock the medium in place.