I am strongly against this, drugs should be only used for medical purpose, otherwise, you won't know what will happen to you.
I advise you not to consume any of the drugs whether they are harmful or not. They have a huge disadvantage to "systeme nerveux" (I don't know the word on english) thus causing a lot of health problems and you can get paraylsed.
Ignore anyone who tells you to try it for fun and be clean
You know it's not that easy to deny them.. willpower is required, and most of people don't have it. I don't know if this happens in your country, but whether a friend is offering you alcohol and you deny it, you're highly judged. And then you go thru stages.. alcohol first, then cigarrettes, then weed and finally cocaine.. this cycle never stops.
Or well I don't really remember your age, probably you're pretty young yet to have perceived this kind of things. I tried alcohol and cigs when I was 14, and weed and cocaine when I was 16 - even after having promised myself that I wasn't going to do so.