I dont even understand weed... I dont even understand smoking.
Put into perspective, smoking does nothing good for you.
Makes breathing more difficult, gunks up your lungs, damages your immune system and makes you more susceptible to sickness, especially that which effects the respiratory system. It makes you stink, yellows your teeth and fingers, decays your teeth, causes 0ral disease, and it certainly doesn't attract too many girls, or make kissing you seem like something desirable. It causes wrinkles and skin discoloration, and takes years off your life. Furthermore it harms the environment, and is a waste of materials that could be put to better use. And why would you want something in your system with the power to cause addiction and influence your mood??
Same things go for weed, except it smells a lot worse and is much less addictive (not to mention illegal).
And a lot of people respond to any of that as being "brain washed" by what you are taught in school or told by parents, but the medical facts are still there and in my opinion, the one brain washed is the abuser of drugs accusing the non-abuser of being brain-washed.