The real danger with cannabis is not that it'll make you sick or have some nasty side effect like this article describes.
The danger is simply that you will like it, you'll end up using it every day, all different times of the day, and it won't really hurt your health as much as it will make you live your life in a somewhat dopey, detached, less-intelligent way. As time goes on it won't feel "fun" it'll just feel "normal". And you just won't get as much out of your life as you could get, won't achieve as much relationship success, professional success, or personal fulfillment.
The danger is simply that you will like it, you'll end up using it every day, all different times of the day, and it won't really hurt your health as much as it will make you live your life in a somewhat dopey, detached, less-intelligent way. As time goes on it won't feel "fun" it'll just feel "normal". And you just won't get as much out of your life as you could get, won't achieve as much relationship success, professional success, or personal fulfillment.