Does cannabis really trigger schizophrenia? Is it true that cannabis is a non-addictive drug? What's the difference between hash and skunk?. According to the UN's estimate, 160 million people around the world use cannabis; that's roughly 2.5 per cent of the world population. Despite these figures, most people have a profound lack of knowledge about cannabis, made all the more dangerous by the changing nature of the drug itself, with much higher levels of potency being seen today than ever before. What You Need to Know About Cannabis offers accessible, accurate and objective information about t.