Crack is smokable cocaine, it just has all of the cut cooked out of the powder form. Meth (speed) isn't much different from coke or crack in what it does to your body and brain, it's just a heck of a lot cheaper to make. They both play havoc with internal organs, and they both, with extended regular use, turn normal people into paranoid psychotics, and that's just what happens to those who avoid over-dosing. I've seen the lives of too many people (some are/were close friends of mine) destroyed by using that stuff.